"Connecting" with my son

My new job has kept me extremely busy and it has been several months since my last post, but I wanted to quickly update on my son's training.  A few months ago I posted how I decided to use a different approach to teaching my two sons than I used to train my two daughters.  Instead of using Lev Alburt's comprehensive chess course and getting right into full games, we are spending the first two years focusing on basic board vision using the three levels of vision and the six piece interactions:

Three Levels of Vision

1. Bottom-up perception.  See the individual piece AND how it moves as one inseparable unit.  See the lines of power (like an aura) emanating from the piece.
2. Top-down processing.  See the six functional relationships between the pieces (see below).
3. Interconnected system.  See the entire board as (5 to 6) groups of pieces with functional relationships (not unconnected sets of individual pieces).

Six Piece Interactions (or "connections")

1. Allied pieces:  (1) directly defend, (2) defend by blocking, and (3) limiting (interfering)
2. Enemy pieces:  (4) attack pieces, (5) attack important squares (restriction), and (6) physical blockade 

Phase 1 spanned the last 14 months and focused on the first two kinds of vision -- seeing a piece AND the squares it can move to as one unit, and understanding the relationships between the pieces on the board.  

One tiny revelation I had in teaching my son had to do with the relationships between the pieces.  Simple terms like "attack" and "defend" were not a problem, but other terms like "limiting/interfering, restricting, blockade" were confusing him.  So...

My son loves legos.  His room is packed floor to ceiling with Scooby Doo, Star Wars, and Minecraft sets that he and I have spent hundreds of hours building together.  So I decided to use the term "connect" to help him see and understand the relationships between chess pieces.  

I first say "connect" for all chess relationships on the board, and once he sees a connection I then switch to use the correct term.  That way I can describe a single group of many pieces that have various connections (attacking, defending, blocking, limiting, etc).  This approach has worked great for us!

Phase 1 is now finished and my son (now 5) has completed the Step Method Stepping Stones 1, Sukhin's Chess Camp 1, and is roughly half way done with two Peshka programs (simple captures, and simple defense).

Phase 2 will cover the next year, and we will include Step Method Stepping Stones 2, Sukhin's Chess Camp 2 and 3, and we will continue with those two Peshka programs and will add other Peshka programs with mate in ones and mate defense.  

Next Blog Series

Now that I have nearly finished my 20+ blog series on calculation -- I am putting the final touches on my last post in the counterattacking series -- there are several other areas I would like to blog about over the next few months:

- tactics -- detailed analysis of the visual and logical elements of the major tactical devices.
- evaluation -- the key elements of evaluation using the KMAP structure.
- endgames -- a focused study of pawn breakthroughs, from the simple to the complex.

All three are incredibly interesting to me...what to do?

Teaching Chess to My Children

When they turned 5, I taught my daughters how to play chess using Lev Alburt’s Comprehensive Chess Course (vol 1 and 2).  My older daughter was not very interested but my younger daughter continued playing and, now 11, is rated 1100 USCF, plays regularly in rated tournaments, and has been the strongest player in her school club since the second grade.

I learned quite a bit over the last several years about how children learn chess, and  for the past year I have been using a totally new approach with my older son.  He just turned 5 this week and I’m nearing the end of “phase 1”.  The point of this blog is to get my thoughts down about how that phase went and outline what phase 2 will look like.

Why did I decide to change my approach?  I believe Alburt's book moves too quickly into complete games, and does not focus on enough on the more fundamental aspects of the game.  He goes from teaching the basic piece movements right into learning how to castle and basic opening theory.  That’s great if you want to just start playing, and I have to say my daughter has done great with this foundation.

But I took an entirely different approach with my son, and I’ll likely use this with my now 2-year old as well, who is already interested in chess from watching his older siblings.  This approach is discussed in the Step Method teacher’s manual, in the introduction to Sukhin’s series, and in some detail at Momir Radovic’s website http://iplayoochess.com/.  I love the ideas on his website, but unfortunately I did not find any suggestions about how to actually implement them (I guess you have to hire him as a coach?).  That’s where Step Method and Sukhin come in.

The core idea is to spend a LOT more energy on basic board vision.  Vision is the fundamental ingredient to all of chess, and there are three things to “see” (this is my summary of ideas from iplayoochess.com):

1. Bottom-up perception.  See the individual piece AND how it moves as one inseparable unit.  See the lines of power (like an aura) emanating from the piece.
2. Top-down processing.  See the functional relationships between the pieces (there are six, see below).
3. Interconnected system.  See the entire board as (5 to 6) groups of pieces with functional relationships (not unconnected sets of individual pieces).

I used three different books (Stepping Stones, Sukhin’s Chess Camp Volume 1, and Chess is Child’s Play) to go through the basic ideas, which I have divided the ideas into three phases, with phases 1 and 2 lasting roughly one year each:

Phase 1 – “pre-checkmate” (covers first two kinds of vision)
Phase 2 – “mate in one, simple threats, and simple checkmates” (covers all three kinds of vision)
Phase 3 – “mate in two, complex threats, and other checkmate patterns” (covers all three kinds of vision)

Phase 1 – The key element of this phase is to use a very small amount of material on the board, and no checkmate (that comes in phase 2).  I have introduced what checkmate is and basic rules like the king cannot step into an attack, and must move if he is being attacked (we do call it “check”).

We first completed almost all of Chess is Child’s play.  This book is really great for teaching basic piece names, and the concepts of move, attack, capture, and defend.  The teaching method used in the book is extremely clear and simple, and there is a lot of great “Q&A” from other parents on each step of the process.  The authors have included lots of ideas for mini-games to play along the way.  There is not a better book out there for teaching these basic concepts, and we took almost six months to slowly work through this material.  We took things at his pace.

Then we started on a mix of Stepping Stones 1 worksheets (from the Dutch Step Method), and 500+ simple positions from Sukhin’s Chess camp.  Both of those books end with checkmate-related issues, so I’m ending phase 1 by introducing those ideas.  Here is a summary of the ideas we covered in phase 1:

• Pieces: names, relative values, and movement
• Board: orientation (light on the right); naming files, ranks, diagonals, and squares; board vocabulary (squares are “light and dark”, pieces are “white and black”); the “center”, etc.
• Vocabulary/Concept of SIX FUNCTIONAL RELATIONSHIPS: 
• Allied pieces:  (1) directly defend, (2) defend by blocking, and (3) limiting (interfering)
• Enemy pieces:  (4) attack pieces, (5) attack important squares (restriction), and (6) physical blockade 
• Other concepts:  undefended pieces, capturing up/down, equal trades, zugzwang, stalemate, alignment, etc.

Some of this might sound too basic or too advanced, but it is all attainable even by a four year old.  The positions in Sukhin’s chess camp are incredibly simple, but for a beginner can be very complicated without knowing these basic interactions.

They key in this phase is to be able to very quickly “see” all the pieces on the board (yes, that bishop all the way in the other corner matters!) along with seeing how the piece moves, and then to understand how all the pieces relate to each other.  These are the first and second “vision” elements outlined above.  This gives ideas about what is happening in the position, and only then can you start to think about what kind of move you should make.

I used a colorful vocabulary to elicit fun (and hopefully meaningful) images about piece movement, and piece interactions.  My idea was to help him create his own images about these fundamental elements of the game that may help him see and feel the piece “auras” and the relationships between other pieces.  I am going to put more work into this vocabulary when I teach phase 1 to my youngest son.

In addition to reviewing the Sukhin/Stepping Stone positions, we play lots of mini-games, and also do easy skill builder exercises in Maurice Ashley’s ‘Learn Chess!’ app.

So phase 1 is now almost over for my older son.  All three books end with checkmate themes, and my plan is to end phase 1 by teaching the core checkmate concepts and vocabulary.  He knows a lot of chess terms and ideas, and seems to genuinely enjoy the game.  So hopefully I’m doing something right!

Phase 2 will be all about checkmate (in addition to drilling phase 1 things).  We will build up from static positions where the quesiton is whether the position is “mate, stalemate, or is there a move”.  Then simple mate-in-ones with one mating piece and no “noise”, then adding more pieces involved in the mate, and then adding more noise (pieces not involved in the mate).  We’ll do the basic checkmates with two rooks, a queen, one rook, etc.  We’ll also do basic endgame stuff like minor pieces plus pawns, minors vs pawns, some piece-only endgames (queen vs bishop, queen vs knight, and maybe rook vs bishop/knight), and lots of king and pawn endings.  There are other concepts I will pack into this phase as well, like more tactical ideas using checks/mate threats, knight forks, etc.  I’ll possibly introduce each tactical idea so he knows the vocabulary and core idea, but we won’t really drill them until later (once he knows checkmate very well).  The other stuff is nice to have, but the core of this phase is checkmate.  Lots of checkmate.

Calculating Forcing Moves: Defensive Idea 5 - Counterattack to DEFEND (Idea 3, move)

In this post we’ll examine a position where there is a real threat on the board, and we will create an EGT in order to allow our piece to escape from the attack.  Thus we are counterattacking in order to allow the use of one of the basic defensive themes (Idea 3, move away).

In the following position black just played …Bf8.  White to move.

2kr1b2/p2p3p/2p2p1Q/3n1bpB/P7/6B1/5P2/6K1 w - - 0 1

Let's evaluate the position, and then find and prioritize all of black’s threats.

Evaluation:  White is down three points (white queen vs black rook, knight, and four pawns), and neither king has great pawn cover.   Black is likely to win the endgame, and white will be fighting for a draw if he can survive the next few moves.

Threats:  Black’s threat is the simple capture of white’s queen with 1…Bxh6, and this is our priority for calculations.  

Let's look at the five defensive ideas to see what options white has to defend against the checkmate.

Idea 1 – do something to the attacking pieces (the f8 bishop).  White can capture the bishop (1. Qxf8) but the resulting position is clearly lost for white.  He cannot pin the bishop to something of equal/greater value, and he cannot deflect the bishop.

Idea 1 has generated zero candidate moves.

Idea 2 – block the attacking pieces (the f8 bishop from h6).  White cannot block the attack.

Idea 2 has generated zero candidate moves.

Idea 3 – move the piece being attacked (the white queen).  Aside from capturing the bishop on f8, the white queen can move to five other squares (Qg7, Qxh7, Qg6, Qxf6, Qxg5), however, none of them are safe and all resulting positions are lost for white.

Idea 3 has generated zero candidate moves.

Idea 4 – reinforce/defend the mating square (the white queen).  Defending the queen is not possible here.

Idea 4 has generated zero candidate moves.

Idea 5 – counterattack with an Equal or Greater Threat (of losing the queen).  Looking at the EGT chart from earlier we can see that in response to an attack against the queen there are several options.  An equal threat would be to attack the queen (or threaten to win nine points of material), but that is not possible here.  A greater threat would be check, or a checkmate threat.  White has zero checks, but here there is a common checkmate pattern (Boden’s mate) and white can threaten to execute it (1. Be2, threatening 2. Ba6#)

Idea 5 has generated one candidate move.

In this process we considered several moves but rejected nearly all of them after a quick check, and we have found one specific candidate move:

In an actual game with only one candidate move, we should just play it and calculate the next steps on our opponent’s time.  Let’s just take a moment to look at the next few moves, in particular how black should defend against the checkmate threat after white’s 1. Be2:

I’ll try out a simplified approach to looking at black’s defenses.  I’ll list the defensive ideas along with the calculation/evaluation, and hopefully this will be easier to follow than a purely narrative approach!

Idea 1 – black cannot capture white’s Be2 or Bg3, and cannot pin the Be2.
Idea 2 – black has 5 blocks, but zero moves that “prepare to” block on b7:

• 1…Bd3 (blocking white’s Be2) 2. Bxd3, and black gives up a bishop and does not prevent the checkmate.  Black can reject this block.
• 1…Nf4 (blocking white’s Bg3, and threatening both 2…Nxe2+ and 2…Bxh6) 2. Bxf4 (renewing the mate threat) gxf4 3. Qxf4 followed by 4. Qxf5.  Black loses a piece and a pawn with this variation, and black should reject this block.
• 1…Bd6 (blocking white’s Bg3) 2. Bxd6 and again black gives up a bishop and does not prevent the checkmate.  Black can reject this block.
• 1…d6 (blocking white’s Bg3, and giving the black king a new escape square on d7) and since there is no checkmate threat, now the queen must move:
• 2. Qh5/h2/h1 and black is winning the endgame, but white can fight for a draw.  
• 2. Ba6+ Kc7 (forced, 2…Kb8?! allows white to win nine points of material for the queen with 3. Qxf8 Rxf8 4. Bxd6+ Ka8 (only) 5. Bxf8, the endgame is still winning for black but I personally prefer to keep the connected pawns c6/d6) 3. Qh5/h2/h1 and black is winning the endgame, but white can fight for a draw.
• NOTE: This is black’s KOTH, since all white replies lead to a winning game for black.  In a real game black could just make this move without calculating further, but let’s see if he has anything stronger!
• 1…Nc7 (blocking white’s Bg3, and defending the a6 square) 2. Qxf6 Be6 Qxg5, and black still has a material advantage but this is less winning for black than 1…d6 lines.  Black should reject this.

Idea 3 – black has one move and two that “prepare to” move:

• 1…Kb7 (also defends the a6 square)
• 2. Qh5/h2/h1 and black is winning the endgame, but white can fight for a draw.  
• NOTE:  Is this any better than our KOTH?  The only difference I can see between this and our KOTH is this position leaves the black king more exposed.  White probably can’t do much but with the white queen still lurking, why risk it?  We don’t have to reject it as bad for black, it’s just not as good as our KOTH.
• 1…d6 (giving the black king a new escape square on d7, and blocking white’s Bg3).  We looked at this above – this is already our KOTH.
• 1…Re8 (giving the black king a new escape square on d8) 
• 2. Qh5 Bg6 3. Qf3 and black is winning the endgame, but white can fight for a draw.  
• 2. Ba6+ Kd8 (only) 3. Qh5 Bg6 4. Qf3 and black is winning the endgame, but white can fight for a draw.
• NOTE:  Is this any better than our KOTH?  In fact, I like that this puts the rook on the open file and the pressure on white’s Be2 limits white’s options.  I could consider this to be our new KOTH by a slight edge.

Idea 4 – black has three moves that defend the a6 mate square:

• 1…Nc7, we looked at this above and rejected.
• 1…Kb7, we looked above and determined was not bad, but not better than our KOTH.
• 1…Nb4 2. Qxf6 Be6 3. Qxg5.  Like the other knight move this undefends f6 and allows white to get back two pawns.  Black should reject this.

Idea 5 –  the only EGT to consider would have to start with a check, and black has none.

Let’s take a look at our final chart:

Conclusion.  Creating a checkmate threat was white’s only real candidate move in the original position because it allowed the queen to escape the attack.  The road ahead will be very tough for white, but he does have some drawing chances.

This is the process you should be able to do mentally:  prioritize the threats, use all five defensive ideas to search for specific candidate moves, calculate each one completely, and then pick the best variation based on the final evaluation.

Calculating Forcing Moves: Defensive Idea 1, Part 4 (Restrict the Attacker, Prepare to Capture)

In earlier posts we examined different ways of implementing defensive Idea 1 (do something to the attacker), including capturing, pinning, and deflecting your opponent’s attacking pieces.  Here we’ll look at another very cool way of doing something to the attacking pieces – restriction, and “prepare to” capture.

In a recent blog post on chess.com, National Master Jeremy Kane posted a position from an online blitz game where his opponent resigned following a tricky move by NM Kane, and only later did Kane see that his opponent had a winning defensive move (the ultimate blunder, Kane says in the post, is resigning a won position!).

In the following position NM Kane had white and just played 1. Rh1.  Black to move.

1r6/6p1/2pR2Bk/2n1pPp1/p1P1P3/1qQ4K/r7/7R b - - 0 1

Let's evaluate the position, and then find and prioritize all of white’s threats.

Evaluation:  Black is up two pawns and has a powerful outside passed pawn supported by all of his pieces, but his king is incredibly weak and has zero defenders.  Black should win the endgame if he can survive the next few moves.  White’s pieces are very active but his king is also exposed.  White is fighting to draw, and his basic plan is to capture black’s pawns (if he can’t checkmate black that is!).

Threats:  White’s threat is the discovered checkmate 2. Kg4+ or 2. Kg3+ followed by 2…Rh2 (only) 3. Rxg2#.  White’s other discovered check (on the 6th rank) could be useful in gaining tempo if we can find a useful square for the bishop, but is not our priority for calculations.  

Let's look at the five defensive ideas to see what options black has to defend against the checkmate.

Idea 1 – do something to the attacking pieces (the g6 bishop, h1 rook, and h3 king).  We cannot capture, pin or deflect the bishop.  We cannot directly capture the rook, however, we can “prepare to” capture the rook by attacking it (with 1…Ra1 and 1…Qb1; if 1…Qd1 2. Rdxd1 and now black cannot stop the discovered checkmate).  We cannot pin or deflect the rook.  We can restrict the king from moving to g3 (with 1…Nxe4, but that fails to 2. Kg4+), and we can restrict both g3 and g4 at the same time (with 1...Rg2, but that fails to 2. Kxg2#).

Idea 1 has generated two candidate moves.

Idea 2 – block the attacking pieces (the h1 rook from h6).  Black can prepare to block on h2 by adding a second blocking piece (1…Qb2/1…Qc2) but white can easily refute both of those (with the simple 2. Kg3+, then capturing twice on h2 after which white is again threatening checkmate with …Qh3#).  Black can prepare to block with the queen on h5 (with 1…Qd1, but per the above variation that fails).

Idea 2 has generated zero candidate moves.

Idea 3 – move the piece being attacked (the white king).  The black king has zero moves.  We can create one escape square (1…g4+, which just encourages the checkmate 2. Kxg4+ Rh2 (only) 3. Rxh2#).  

Idea 3 has generated zero candidate moves.

Idea 4 – reinforce/defend the mating square (the h1 square).  Since the threat is not to move the rook to h1, but to discover the rook’s attack by moving the white king, there are no moves that defend h1 that we did not already consider above using Idea 1, and we already considered moves that restrict the black king under Idea 1.

Idea 4 has generated zero candidate moves.

Idea 5 – counterattack with an Equal or Greater Threat (of checkmate).  Looking at the EGT chart from earlier we can see that against a checkmate threat, you can only counterattack with a check.  Black has three checks in this position (1...Qxc3+, 1…g4+, are both refuted by 2. Kg4+; and 1…Rh2+ is refuted by 2. Rxh2 and now black cannot stop the discovered checkmate).

Idea 5 has generated zero candidate moves.

This process has generated two specific candidate moves:

The next step is to calculate both candidates.  Since neither move is particularly forcing, let’s try to first refute the apparently bad queen move 1…Qb1:

Black is now threatening checkmate himself (with 2…Qxh1+ 3. Kg3/Kg4 Qh4+ 4. Kf3 (only) Qf4#), and is also prepared to pin the queen (with …Rb3).  Black’s rooks and knight are well-placed (although seemingly uncoordinated) to support his passed pawn too, so I’d evaluate that black is winning here, and that white should be fighting for a draw.  Let’s see if white can prevent the checkmate.

White can capture the queen (2. Rxb1), he has four blocks (2. Qc1, 2. Qe1, 2. Rdd1, and 2. Bh5+/3. Bd1), he can move the rook (2. Rh2, 2. Re1, 2. Rd1, 2. Rc1), he can defend the rook (2. Qf3, 2. Bh5+/3. Bf3), and he can counterattack with a greater threat (check) using the two discoveries, but Kg3/Kg4 fails to the queen capture, and it is not clear where the g6 bishop might go (he only has four squares) that we haven’t already considered.

That gives us 11 candidates to consider.

Let’s start with the most active move (and seemingly obvious refutation of black’s play), the capture 2. Rxb1:

2…Rxb1 (threatening 3…Rb3) and now I like 3. Bh5+ Kh7 (forced; 3…Kxh5? 4. Qf3+, and both blocks seem pointless) 4. Bd1 (defending b3) 4…Nxe4!? 5. Qxe5 (where else?) Nf2+ 6. Kg3 (forced) Nxd1 and even though material is exactly equal (rook, knight and two pawns vs queen) black is again threatening checkmate with 7…Rb3+ 8. Kg4 (forced, both blocks are pointless) Rg2+ 9. Kh5 (only) Rh3#.  That means moves like 7. Qe8 that threaten mate in 2 are too slow, and white now must defend against the checkmate.

White can’t capture, pin, or deflect the rooks or the g5 pawn.  White can prepare to block (with 7. Rd3, or 7. Qe4 to play 8. Rd3 while also attacking the b1 rook, and setting up a discovered check).  White can move his king (7. Kf3, 7. Kg4, 7. Kh3), and he can create an escape square on f5 (7. f6).  White can defend the b3 square (but we already looked at Rd3), and can defend g2 (we already looked at 7. Qe4) but cannot defend h3.  White’s counterattacks must begin with a check because of the checkmate threat, and we have two (7. Qxg7+, 7. Rh6+).

This has generated eight candidate moves for white.  

Let’s start by looking at the most forcing moves first, the two checks.  I don’t see any clear follow up after 7. Qxg7+ Kxg7, so let’s calculate the rook check and see if white can at least pull out a draw, so now 7. Rh6+:

7…gxh6 of black’s three options, the pawn capture avoids the checkmate and the forced draw (if 7…Kg8? 8. Qe8#; if 7…Kxh6 8. Qe6+ forces draw by repetition) but it is not clear where this leads after the obvious follow-up 8. Qe7+ Kg8 (or 8…Kh8).  White has been able to force the black king away from the white king so black’s mate threat is no longer looming, but black has a five point material lead following the rook sac while white’s only plus is the position of his queen unopposed against the black king.

Thinking back to the goals of counterattacking (win, draw, defend), white can threaten mate in one (9.f6), but he can’t capture either of black’s rooks (even though they are both loose) since both light diagonals are blocked by his own pawns. I can see that stalemate is not an option for white because of the mobility of his pawns and king, but he can force a repetition (9. Qe8+).

That gives us two candidate moves for white.

Before bailing out into the draw or looking for more defensive moves, let’s see where the most forcing move leads us after the mate in one threat, 9. f6:

Black cannot capture, pin, deflect, block the queen or pawn, and he can’t move his king to escape.  He can defend g7 (9…Rb7, but that just loses the rook), and black’s counterattacks must begin with a check because of the checkmate threat, and we have three (9…Ra3+, 9…Rb3+, 9…Rg2+).  Of black’s three checks, the most promising seems to be 9…Rb3+:

10. Kg4 (forced) and now it is not at all clear that black can do anything useful with his last few checks.  He could try to defend the g7 mate square with 10…Ne3+ 11. Kh5 (forced) Nf5, but that fails to the simple 12. Qe6+, picking up the knight.

I don’t see a clear defense for black, so we can reject black’s move seven (7…gxh6).  His only alternatives at move seven allowed checkmate or draw by repetition (7…Kxh6 8. Qe6+), which so far appears to be black’s KOTH.

While most of the play in that line was forced for white, white does have another 10 candidate moves to consider at move two.  Do any of them lead to a position that is better than a draw?  We have only considered 2. Rxb1, but we still have four blocks (2. Qc1, 2. Qe1, 2. Rdd1, and 2. Bh5+/3. Bd1), four rook moves (2. Rh2, 2. Re1, 2. Rhd1, 2. Rc1), and two moves that defend the rook (2. Qf3, 2. Bh5+/3. Bf3).

So where do we start with those 10 remaining moves?  Are any of them particularly forcing, or can any of them be quickly rejected as bad.  Scanning quickly – and not really calculating – most of them look bad for white.  The four blocks and the four rook moves all seem to allow black to play 2…Rb3 (with or without check), which does not look good for white’s health…although some appear less bad than the others.  But the two moves that defend the rook are in fact extremely forcing!  Rerouting the bishop to f3 to defend the rook comes with check and relieves white of black’s …Rb3 threat.  However, the more interesting move both defends the white rook AND threatens checkmate in one move!  If there is a refutation of black’s 1…Qb1, this is probably going to be it!  Let’s see if white can get better than a draw by playing 2. Qf3:

The only thing better than a mate-in-1 threat is TWO checkmate threats!  This candidate move does just that with the new mate-in-1 threat of 3. Qh5#, and the mate-in-3 threat of 3. Kg4+/Kg3+ Qxh1 4. Qxh1+ Rh2 5. Qxh2#

It is very difficult to see an obvious defense for black, because what defends against one checkmate seems to encourage the other!  Let’s see what we can find.

We can capture the rook on h1 (2…Qxh1+), and pinning the queen is something that would normally be very powerful but here it fails completely (2…Rb3? 3. Kg4+ Qxh1 4. Qxh1+ Rh2 5. Rxh2+ Rh3 6. Rxh3#).   We can block the queen from getting to h5 (2…g4+) but that just encourages the other mate (3. Kxg4+), and we can prepare to block the mate-in-3 (2…Rbb2) but that does nothing to prevent the mate-in-1.  We cannot move the king, and creating an escape square just encouraged the mate-in-3 (2…g4+ 3. Kxg4+).  We can defend h5 (with 2…Qd1) but that does nothing to stop the other (3. Kg4+).  Our counterattacks must start with a check, and of black’s four checks there are only two we have not yet considered but they both appear to be easily refuted (2…Rh2+ 3. Rxh2; and, 2…Qf1+ 3. Kg4+).  That gives us only one candidate move to consider for black, so let’s see if black can get at least a draw with 2…Qxh1+:

3. Qxh1 looks like the best of white’s three possible replies, and again white is threatening checkmate.  The only move I can find from the five Ideas that addresses the checkmate is the move that prepares to block the check with 3…Rbb2. Now white might have better but he can at least force simplification to a won endgame with 4. Kg3+ Rh2 (only) 5. Qxh2+ Rxh2 (only) 6. Kxh2.

This line after 2. Qf3 is clearly much better for white than the more obvious original move capturing the queen (2. Rxb1), and is a very clear refutation of black’s first candidate move (1…Qb1).

What about white’s other nine candidate moves?  Well, since we already found one reply (of the 11) for white that is clearly winning, black can reject his initial candidate move without further calculation.  Sure, white might have an even stronger reply, but this one refutation is all black needs to see in order to reject his candidate move.  If black were to actually play that move, white could consider using some additional time to look for something even stronger than Qf3, which would be a great situation for white!

So having found white’s refutation, black can reject his candidate move 1…Qb1, and we can update our chart with what we have learned so far.

Let’s see if black can hold on to the position and avoid the loss with his only other candidate move 1…Ra1:  
Black’s threats are now to win white’s pinned queen and h1 rook (both are capture-checks), and checkmate is very likely to follow.  White can capture the queen and the rook, but both moves appear to fail.  For example if:

2. Qxb3 Rxh1+ 3. Kg2 axb3 and now it looks impossible to stop black’s a-pawn from promoting.  Or if instead 2. Rxa1 Qxc3+ 3. Kg4 Qxa1, and black is clearly winning.

White can’t pin either piece.  He can’t block the queen, but he can block the rook (2. Rdd1) but that fails (2…Rxd1 3. Rxd1 Qxc3).  Queen moves along the 3rd rank (due to the pin) all fail.  There are no safe squares for the rook along the first rank, and only one square along the h-file that appears safe (2. Rh2).  He can defend the queen (2. Rd3) but that fails as well (2…Rxh1+ 3. Kg2 Nxd3).  We have already looked at one move that defends the rook (2. Rdd1) which we determined was not good.  That only leaves counterattacks.  We already have one equal threat (against the queen) that we determined is not actually a threat at all, and a greater threat would consist of mate threats or checks.  We have already considered moving the rook to a square that maintains the mate threat (2. Rh2), and it does not look like any of our eight checks get us anywhere.

So that really only leaves one candidate move for white, 2. Rh2:

White is again threatening checkmate in one move (3. Kg3#/3. Kg4#), so let’s again consider the five defensive ideas and see if black can hold on:

Black cannot capture the h2 rook, but he can prepare to capture (2…Rb2, and 2…Rh1 but the latter obviously fails).  Pinning the rook wouldn’t help here, but he can prevent the king from moving to both g3 and g4 (2…Rg1).  He can prepare to block on h5 (2…Qd1, but that fails to stop the checkmate 3. Kg3+ Qh5 4. Rxh5#).  He cannot move his king and creating an escape square (2…g4+) just encourages the checkmate (3. Kxg4#)!  That only leaves counterattacks, which must begin with a check, and there is only one check we have not yet considered (2…Qxc3+) but that also just allows white to checkmate.

That gives black two candidate moves.

Preparing to capture the rook (2…Rb2) just allows the position to repeat and doesn’t seem to make much progress, but we might come back to it if black’s other candidate move fails to impress, after 2…Rg1:

Black’s threat is to checkmate starting with the capture-check (3…Qxc3+ 4. Rd3 (only) Qxd3#).  White can capture the queen, but that just forces checkmate.  He cannot block the queen, and the queen has no safe squares on the 3rd rank.  He can defend the queen (3. Rd3, and 3. Rc2), and can counterattack with a greater threat using the discovered check but where to put the bishop?  Now if Bh5+ black can take the bishop since the white queen can no longer swoop in to deliver checkmate due to the pin (like the earlier lines with Qf3+) and white does not have the discovery on the h-file.  That only leaves three squares (Bh7, Bf7, and Be8) none of which allow the bishop to reposition to a more useful square.

That gives white two candidate moves.

Both look really bad for white.  Let’s start with 3. Rd3:

The natural 3…Nxd3 now threatens checkmate (4…Nf4#).  White can’t capture or pin the knight or the queen.  He can’t block the knight from getting to f4.  He cannot move the king but he can create an escape square by moving his rook on h2, however that fails to Qxc3 (perhaps following a check or capture-check, in case of 4. Rg2 Rh1+ first).  He can defend f4 four ways but the all fail (4. Rf2 Qxc3; 4. Qc1/Qd1/Qxe5 Nf4# (double checkmate)).  Counterattacks must begin with a check, and white has none.

With zero viable candidate replies for white we can conclude that black's 3…Nxd3 refutes white's 3.Rd3, so let’s look at white’s only other candidate move 3. Rc2:

And now simplifying to an endgame looks good enough for black to declare victory after 3…Qxc3+ 4. Rxc3 Nxe4

Let’s see what our final chart looks like:

Conclusion.  So this process has shown us that black has one and only one defense to white’s checkmate threat using two new variations on the first defensive idea of “doing something to the attacker”:  prepare to capture, and restrict.  These two ideas themselves are rather sophisticated and we had to go many ply deep to prove that the first candidate was bad for black.  What I found interesting about the calculation process here was in the refutation of black's candidate move 1...Qb1.  The obvious-looking capture (2. Rxb1) only allowed a draw, but the move that both defended and counter-attacked (2. Qf3) which was not totally obvious to find is what wins for white.  I'm not sure of any other calculation process that would have lead to finding that move!

This is the process you should be able to do mentally:  prioritize the threats, use all five defensive ideas to search for specific candidate moves, calculate each one completely, and then pick the best variation based on the final evaluation.  And now you have two new tools in your defensive calculation toolkit -- preparing to capture the attacker, and restricting the attacker.  It is possible that these ideas only come into play for certain discovered checks (obviously this wouldn't work for discovered checks that are double checks!).

Calculating Forcing Moves: Defensive Idea 5 - Counterattack to DEFEND (Idea 1, capture)

In the last few posts on counterattacking we created Equal or Greater Threats (EGT) that allowed us to force a WIN, and to force DRAWs (by stalemate, repetition, and material).

The next few posts will look at “counterattacking to DEFEND”, which is using EGTs to allow the use of one of the first four defensive ideas:

• Defensive Idea 1 – do something to the attackers (capture, pin, deflect, restrict);
• Defensive Idea 2 – block the attackers
• Defensive Idea 3 – move the piece being attacked
• Defensive Idea 4 – defend the piece/square being attacked

In this first post we will use an EGT to allow us to use defensive Idea 1, capture the attackers.  How is this different from Idea 1?  The key difference is tempo, as I’ll explain below.

Black just played 1…Nf4.  White to move.

1k1r4/1b2R2p/p1qP4/1p2Q3/1P3np1/P7/2P2PPP/3R2K1 w - - 0 1

Let's evaluate the position, and then find and prioritize all of black's threats.

Evaluation:  White has a two point material advantage (rook and three pawns vs bishop and knight).  White’s pieces are actively placed, his king is less exposed than black’s, and his advanced passed pawn is a major strength.

Threats:  Black’s threat is 2…Qxg2#, as well as …Ng6 forking white’s queen and rook.  The checkmate threat is clearly our priority for calculations.

Let's look at the five defensive ideas to see what options white has to defend against the checkmate.

Idea 1 – do something to the attacking pieces (the c6 queen, f4 knight, and b7 bishop).  We cannot capture or pin (must be absolute) the queen.  We can capture black’s f4 knight, but quickly see that is easily refuted with 2…Qxg2#.
We can also capture black’s b7 bishop.  This is a perfect opportunity to discuss the difference between Idea 1, and Idea 5.  Take a look at the below position, in particular how the new position of the black king (now on a8) changes things.

1k1r4/1b2R2p/p1qP4/1p2Q3/1P3np1/P7/2P2PPP/3R2K1 w - - 0 1

With the black king on its new square, capturing the bishop now does nothing to prevent the checkmate because 2. Rxb7 Qxg2#.  In this modified position neither of the captures we found using Idea 1 would work since black would still be able to checkmate with 2…Qxg2.

But in the original position with the black king on b8, taking the bishop now comes with check (2. Rxb7+) and black has to spend his next move getting out of check instead of delivering checkmate.  A capture-check should always be appreciated for the extra time it gains.  Sticking rigidly with the structure of this blog series I will put this capture-check under Idea 5 because the check is a GREATER threat than the checkmate threat.  However, this capture-check could easily be found by searching the board using either Idea 1 or 5.  Idea 1 has generated zero candidate moves.

Idea 2 – block the attacking pieces (the c6 queen from getting to g2).  White has four blocks (2. Rd5, 2. Qd5, 2. Qe4, and 2. f3).  Both of the queen blocks are very clearly bad for white after the immediate captures.  Only the rook and pawn blocks seem like viable candidates.   Idea 2 has generated two candidate moves.

Idea 3 – move the piece being attacked (the white king).  Since we have time, the king can prepare to move with 2.Kf1, allowing him to escape to e1 if 2…Qxg2+.  Moving the king the other direction (2. Kh1) still allows 2…Qxg2#.  Idea 3 has generated one candidate move.

Idea 4 – reinforce/defend the attacked square or piece (the g2 square).  The are two moves that defend g2 (both 2. Qd5 and 2. Qe4), however, we have already looked at both of these moves under Idea 2 and quickly rejected them.  Idea 4 has generated zero candidate moves.

Idea 5 – counterattack with an Equal or Greater Threat (of checkmate).  Looking at the EGT chart from earlier we can see that against a checkmate threat, you can only counterattack with a check.  White has two checks in this position (2. d7+ and 2. Rxb7+).  Idea 5 has generated two candidate moves.

This process has generated five specific candidate moves:

The next step is to calculate all five candidates starting with the most forcing move, the capture-check 2. Rxb7+:

2…Kxb7 seems the best of black’s four possible replies (two king moves, and two captures), since it keeps the checkmate threat alive, keeps two attackers on white’s passed pawn, gets the king more active, breaks white’s discovered check, and keeps the queen on the c-file attacking the c2 pawn.  Now, since black is still threatening checkmate in g2 white needs to defend, and we see we can now simply capture another attacker (using Idea 1) with 3. Qxf4.  White has traded his rook for two minor pieces and is up three entire pawns.  So far this variation looks very promising for white…but it is not over yet.   3…Qxc2 again threatens mate in 1, but white can regain the pawn and defend his rook (Idea 4) with 4. Qxg4, after which black has no clear refutations.  White is up three pawns, and is winning.  That makes Rxb7+ our King of the Hill (KOTH).

Let’s see if white’s other candidates can force a position that is better than our KOTH, starting with the next most forcing move 2. d7+:

2…Ka8 looks best for black (out of his five possible replies), since it renews the checkmate threat with the fewest complications.  White will be hard pressed to prove that this variation is better for him than the first variation since this leaves black with too much play.  White is again forced to defend against the checkmate, and now only has one check that is clearly bad (3. Qb8+), has the one bad capture (3. Qxf4) from Idea 1 that fails to prevent the checkmate, the same four blocks as above (3. Rd5 and 3. f3 were the only viable options), and he can still move his king (3. Kf1).

Since none of these three options force black to respond, let’s see if we can quickly eliminate any of them as clearly bad.  The rook block seems to be the worst of the three since black can just capture, but let’s see if white gets any compensation:

3. Rd5 and black can just simplify to a won endgame with 3…Qxd5 (the most direct refutation, since black is now threatening checkmate on g2 and d1) 4. Qxd5 (forced) Bxd5 5. Re8 (promotion tricks seem like white’s only hope) Ne6 and black defends his rook and wins.  So we can clearly reject that block.

White’s other two candidates (after 2. d7+ Ka8, and now 3.f3 or 3.Kf1) expose the king to checks which certainly does not help white’s cause, but let’s see if white is still able to force a better position than our KOTH:

3. Kf1 and black can now get very active with two checks 3…Qc4+ and 3…Qxg2+, and the knight fork 3…Ng6.  It is very hard to imagine any of these are any good for white, but let’s just look at 3…Ng6 and see if white has a forced win (better than our KOTH of plus three pawns).

White is yet again on the defensive, and black's threat is to capture his queen (4…Nxe5).  We cannot capture, pin, or deflect the knight (Idea 1), and we can never block knights (Idea 2).  We can move the queen to several safe squares (Idea 3) but they all appear to be easily refuted (after…Qxg2+ followed by …Nxe7), and defending the queen does not make sense (Idea 4).  That only leaves counterattacks (Idea 5).  We can create an equal threat by attacking the queen with either rook (Re6 or Rd6) but black first evades the attacks with …Qxg2+ and then captures our queen.  An interesting counterattack -- and possibly forcing a more winning position than our KOTH -- is to force the promotion of the pawn with 4. Re8:

4…Nxe5 5. Rxd8+ Ka7 (forced, the bishop/queen blocks allow the promotion) 6. Ra8+ Bxa8 7. d8=Q and now white is up one point in material (rook and pawn vs bishop and knight), but alas this is NOT better than our KOTH, and it is black's turn to move and he at least gets his pawn back with 7…Qxg2+.  Even though this forced variation can continue black gets to have all the fine and is likely to win more material.  This is more than sufficient to reject our other candidate move 2. d7+.

That leaves us with three other candidates.  None of them are particularly forcing so it is extremely unlikely that they will be better than our KOTH.  Let's see if we can eliminate any of them as clearly bad.

Our rook block looks losing since after 2. Rd5 Nxd5 white is simply down material, and even though there is some play left he's running out of pieces and will be struggling to even draw.  We can reject this block.

White's other block (2. f3) and the king move (2. Kf1) both expose his king allowing black's pieces even more potential activity.  Let's see if our block somehow gives white a better position than our KOTH, after 2. f3:

White is threatening to capture black's knight.  His discovered check buys him an extra move, but it is not clear that there is a specific threat behind it other than trying to force promotion by following up with Re8.  So white's primary threat is to capture the knight.

We cannot capture, pin or deflect the queen (Idea 1).  We cannot block the queen since it is an 'in-your-face' attack (Idea 2).  We can move the knight (Idea 3) to all eight squares, but the fork (2…Ng6) seems most interesting.  We can defend the knight (Idea 4) two different ways (2…Rf8 and 2…Qc4).  We cannot create an equal threat since white does not have any minor pieces, but we can create a greater threat by attacking his rook and threatening mate (2…Qxc2), or giving check (2…Qb6+).  Of course the most forcing of these five candidates is the check 2…Qb6+:

3. Qc5 is white's most forcing defense (of six possible replies) and limits black's play the most, but I don't see how this is clearly better for white.  We can reject this check for black, and look at his next most forcing move two candidate, the other counterattack 2…Qxc2:

Black is again threatening checkmate, and we can consider this a refutation to white's block (2. f3) but let's play this out a bit further and see if white can pull off something better than our KOTH.  He can capture the knight (Idea 1), but that allows black to take his rook with check.  He can block the queen from getting to g2 (Idea 2) two different ways, but both blocks just lose material.  He can move his king (Idea 3), but one leads to checkmate anyway (3. Kh1 Qxg2#) and the other just loses the rook (3. Kf1 Qxd1+).  He cannot add another defender to g2 (Idea 4) that we haven't already considered under Idea 2.  The only counterattack (Idea 5) possible must begin with a check given the threat of checkmate, and he has two checks (3. d7+ and 3. Rxb7+).  Let's start with the most forcing the capture-check 3. Rxb7+:

Hey wait!  That's the exact same capture-check from the first position, which we know will allow us to next capture the knight.  This must be right!  And it would be except for one key difference.  3…Kxb7 4. Qxf4 Qxd1+! 5. Kf2 (only) and now black is winning.  Of course white does not have to capture the knight, and he can instead give check (4. Qe7+ is the most forcing since it also attacks the rook).   Even though there is more play for white in this line, we can reject it since white can't bring his rook into the attack with check, and he has the same dilemma of how to defend against checkmate (Qxg2#) and the capture-check (Qxd1+) at the same time.  He might be able to get equality but won't be able to force a position better than the KOTH so we can reject 3. Rxb7+.  All of white's other replies at move three were rather passive (the discovered check just buys one move but does not change the position), and are even more unlikely to force a better position than our KOTH.  Since there were no other moves in this variation for white to consider, we can drop this candidate.  Here's what our updated chart looks like:

The last candidate we have to consider is the king move (Idea 3) 2. Kf1:

2…Qxg2+ 3. Ke1 (only) Qg1+ 4. Kd2 (only) Qxf2+ 5. Kc1 (forced, 5. Kc3 Qf3+ looks good for black) Ng6 and black has equalized the material (rook and pawn vs bishop and knight) and it is not clear that white can keep his rook since now his capture-check (Rxb7+) only picks up one minor piece.  Even though there is a bit more play for white in this line, I do not see how from here he can force a position better than our KOTH.  So we can reject this variation as well.

Here is our final chart:

Conclusion:  This process has shown us that white has several candidate moves to consider in the initial position, and by calculating the most forcing moves first we defended against the checkmate and found the forced win!  In a real game we would not need to calculate as much as I did here.  Once we calculated that our most forcing candidate at move one (the capture-check Rxb7+) was winning, we could make the move and enjoy the rest of our win.  But for the sake of this exercise I went ahead and tried to prove that the other candidates were not as good as our KOTH.  

This is the process you should be able to do mentally:  prioritize the threats, use the five defensive ideas to search for specific candidate moves, calculate each one completely, and then pick the best variation based on the final evaluation.

In the next post we will look at positions where we use EGTs to rearrange our pieces to allow another of the basic defensive ideas (from Idea 1-4).

Calculating Forcing Moves: Defensive Idea 3, Part 2 (Prepare to Move)

When your opponent creates a (real) threat, or you are considering creating one against your opponent, there are five defensive ideas to consider.  We have already looked at different ways to implement the first two defensive ideas:  Idea 1 (capture the attacking piece, pin the attacking piece, deflect the attacking piece), or Idea 2 (block the attacking piece).  We also explored the third basic idea of moving out of the attack.

In this post we will look at a position where we "prepare to move".  These moves are possible when the threat is one move away, and you have time to move another piece out of the way so that you can escape to, or through, that square when the threat is played.

The general process is to evaluate the position, identify and prioritize all threats, and then to use the five defensive ideas to identify specific candidate moves.  Next, calculate each candidate move to the end and evaluate the final positions (material and activity).  As you progress through the candidates, keep in mind the "king of the hill" (KOTH) candidate move to help you pick the best at the end.

The below position is from Ward Farnsworth's wonderful chesstactics.org website, but the analysis here is my own!  We'll follow the same approach as usual:  evaluate the position, identify and prioritize all threats, use the five defensive ideas to identify specific candidate moves, and calculate each candidate to find the best (or least bad) reply.

Black just played ...Qe7.  White to move.

5k2/pb2qp1p/1p6/6R1/3p4/8/PP4PP/R2N3K w - - 0 1

Let's evaluate the position and then find all of black's threats.  Black is up a queen and a pawn vs two rooks, and black's pieces and passed pawn are significanly more active than white's pieces.  Black is playing for a win and white is fighting to draw.  Black has two concrete threats:  checkmate (...Qe1#) and win a rook (...Qxg5).  Of those two threats, the checkmate is the priority.  Let's look at the five defensive ideas to see what candidate moves we find, and then pick the best move.  Hopefully we can avoid checkmate AND save the rook.

Idea 1 (capture, pin, deflect):  none.
Idea 2 (block):  1. Re5 and 1. Ne3 directly block the queen from getting to e1, while 1. Rf5 "prepares to" block on the next move with Rf1.
Idea 3 (move):  since the mate is one move away we can look at direct king moves, as well as moves that create an escape square ("prepare to move").  The king only has one move, but 1. Kg1 does not allow the king to escape checkmate because f2 will be covered by the queen on e1.  White can also "prepare to move" his king by creating an escape square on h2 (the bishop is taking away g2), by playing 1. h3 or 1. h4.
Idea 4 (defend):  white can defend the mating square on e1 with his rook on a1, if the knight can get out the way.  We already have 1. Ne3 from above, which we now see might accomplish two things at once (block the queen, and allow the rook to defend e1).  The knight has two other possible squares to move to 1. Nc3 and 1. Nf2.
Idea 5 (counterattack with an equal or greater threat to WIN, DRAW, DEFEND):  there is not time to create equal threat.  A greater threat would have to start with a check, and white has 1. Rg8+.

The five defensive ideas have given us eight actual candidate moves to calculate further:  1. Re5, 1. Ne3, 1. Rf5, 1. h3, 1. h4, 1. Nc3, 1. Nf2, and 1. Rg8+.  Let's start with white's most forcing candidate move 1. Rg8+:

1...Kxg8 (only).  White has lost a rook and has no more checks.  He therefore cannot force a draw by perpetual and is not able to reposition his other pieces to defend using the other four ideas.  Reject 1. Rg8+.

None of the remaining seven moves seem particularly more forcing than the others, so let's just go through them in the order that we discovered them.  1. Re5:

1...Qxe5 appears to be black's most forcing reply.  Black is again threatening mate with no new defensive options available and after 1. Nf2 black is ahead a queen and a (passed) pawn vs a rook, so 1...Qxe5 appears to refute white's candidate.  Reject 1. Re5.

The other block we found also defended e1, so let's next look at the interesting 1. Ne3:

1...Qxg5 appears to be black's most forcing reply, so let's see if that is a refutation.  White is now down more material and black again has two concrete threats:  to capture the knight and, should the knight move, to deliver checkmate with Qxg2#.  Simply pushing the d pawn also looks like a fun attacking idea for black, and would give white a third threat to have to defend against.  Saving the knight (and defender of g2) is white's first priority so let's look at the five defensive ideas and see if any work.  White cannot capture, pin (2. Rd1 doesn't work), deflect, or block the pawn or queen.  He can only move the knight to two squares that do not immediately allow mate (2. Ng4, and 2. Nd5).  He can defend the knight with 2. Re1 but, after 2...dxe3 the rook cannot recapture on e3 because of the mate threat on g2.  That only gives us two defensive ideas, both of which just delay the mate in 1 by one more move.  Then after the obligatory 3. Rg1, black's two threats (passed pawn and checkmate) will make for a simple win, and we can safely say that 1...Qxg5 refutes white's candidate.  Reject 1. Ne3.

The last blocking idea we found prepares to block on f1 after Qe1+, but seems easily refuted.  After 1. Rf5:

1...Qe1+ 2. Rf1 (only) Qxf1#.  Yup, easily refuted.  Reject 1. Rf5.

Next up would be the two candidate moves that create an escape square for the white king, and prepare for him to move out of the check.  Let's look first at 1. h3:

1...Qe1+ is black's most forcing move, but after the king moves away with 2. Kh2, black has no clear follow-up.

1...Qxg5 appears stronger for black, since he is now up even more material and is threatening checkmate on the next move with ..Qxg2.  After considering all five defensive ideas, we find whites' only move to prevent the mate is 2. Ne3 following by 3. Rg1.  So while 1...Qe1+ does very little for black, 1...Qxg5 is a crushing refutation.  Reject 1. h3.

The other block seems much more interesting because it also defends the rook on g5, so let's see if black has anything left after 1. h4:

1...Qe1 (again black's most forcing move) 2. Kh2 (only) Qxh4+ 3. Kg1 (only) Qxg5 4. Ne3 (forced) dxe3 5. Kf1 (only way to prolong...) Qxg2+ 6. Ke1 Qf2+ 7. Kd1 (only) Qd2#.  Reject 1. h4.

The final two candidate moves (1. Nc3 and 1. Nf2) come from the idea of defending the e1 mate square.  Since 1. Nc3 puts the knight en prise, let's see what we get with 1. Nf2:

1...Qxg5 (most forcing) 2. Rg1 (forced) and now Qd2 appears simple and wins at least the b pawn (defending the pawn with 3. Nd1 allows Bxg2+ 3. Rxg2 (only) Qxd1+ 4. Rg1 (only) and now black has won a pawn and traded the minor pieces but also has ...Qf3+ followed by ...d3.).

White's last defensive hope is 1. Nc3:

1...Qxg5 (most forcing) 2. Rg1 (forced) and now black just picks off the c3 knight, making this line worse than 1. Nf2.

After looking at eight candidate moves, we can confidently resign knowing that we have not missed a single defensive opportunity for white.  If we felt compelled to play on for some sadistic reason, the two least bad moves would be either 1. Rg8+ or 1. Re5, which "only" leave black ahead a queen and passed pawn vs a rook.  All other moves are worse than that!  In future posts I will discuss ways to track multiple evaluations in your head while calculating, including positions where all of your choices are relatively bad or your best move is only slightly better than the second best!

Calculating Forcing Moves: Defensive Idea 2, Part 2 (Prepare to Block)

When your opponent creates a (real) threat, or you are considering creating one against your opponent, there are five defensive ideas to consider.  We have already looked at three different ways to implement the first defensive idea of going after the attacking piece:  capture the attacking piece, pin the attacking piece, or deflect the attacking piece.  In an earlier post we looked at the second defensive idea of blocking the attack.

In this post we will look at a position where the threat is not immediately on the board but is likely to be played on the next move (like a mate-in-1 threat), and we will use the idea of "prepare" to block" by rearranging our pieces to allow a block if the threat is executed.  

The general process is to evaluate the position, identify all threats, and then to use the five defensive ideas to identify specific candidate moves.  Next, calculate each candidate move to the end and evaluate the final positions (material and activity).  As you progress through the candidates, keep in mind the "king of the hill" (KOTH) candidate move to help you pick the best at the end.

The next position uses the same basic defensive idea of blocking an attack, but also demonstrates how blocking with a like piece can gain time and be more forcing than blocking with other pieces.

Black just played Qe6+.  White to move.

r4r2/4ppBk/p2pq1p1/1p5n/4P2P/P4P2/KPPQ4/3R1BR1 w - - 0 1

Let's evaluate the position and then find all of the threats.  Pawns are equal, both sides have one queen and two rooks, and although white is currently up a minor piece his bishop on g7 is en prise and he is in check.  Will white have time to save his bishop?  Black's threats are the check, and then to capture the g7 bishop on his next move, after which material will be equal.  White is also threatening checkmate with Qh6#, but needs to address both the check and the threat to his g7 bishop.  Let's look at white's three defensive ideas (you can't defend or counterattack when in check!) to see what candidate moves we find, and then pick the best move.

Idea 1 (capture, pin, deflect):  none.
Idea 2 (block):  searching square by square between the queen and the king we find four moves that block the check: 1. Qd5, 1. c4, 1. Bc4, and 1. b3.
Idea 3 (move):  1. Ka1, and 1. Kb1
Idea 4 (defend):  n/a
Idea 5 (counterattack with an equal or greater threat to WIN, DRAW, DEFEND):  n/a

Let's look at the easiest to calculate moves first (instead of the most forcing).  After both king moves, black just captures the bishop (if 1. Ka1/Kb1 Kxg7) and the position is materially equal.  This is our KOTH.

Now let's look at calculate each block and see if we get anything better than our KOTH evalulation of equal.

If 1. Qd5 white has no threats (because Qh6# is no longer an option) and black can simply take the bishop, or can take the queen first with check and then the bishop.  Black has nothing better, and this line is no better (and no worse) than our KOTH.

If 1. c4 white now has one threat to deliver mate with Qh6#.  Black can easily address the one threat threat by capturing one of the attackers with Kxg7.  Black has nothing better, and this line is no better (and no worse) than our KOTH.

If 1. b3 again white now has one threat to deliver mate with Qh6#.  Black can easily address the one threat threat by capturing one of the attackers with Kxg7.  Black has nothing better, and this line is no better(and no worse) than our KOTH.

If 1. Bc4 white now has two threats - to capture the queen, and to deliver checkmate.  The checkmate is the greater threat so lets look at black's defensive options.

Idea 1:  Black can capture the g7 bishop with 1...Kxg7 or 1...Nxg7.
Idea 2:  Black can block the white queen from getting to h6 with 1...Nf4 and 1...g5.
Idea 3:  Black can defend the mating square on h6 again with 1...g5.
Idea 4:  The black can escape with 1...Kg8.
Idea 5:  Black's counterattack ideas must begin with a check, given white's checkmate threat, and black only has one:  1...Qxc4+

Of black's six candidate moves we can quickly dismiss five -- the two captures, the two blocks, and the move -- because they all immediately lose the queen.  That only leaves black's one counterattack idea, so after 1. Bc4 Qxc4+:

We have the same exact same situation as in the starting position, except now white is down an entire piece and, as soon as white addresses the check, black is going to capture the g7 bishop.  This would leave white down an entire piece and appears to refute white's 1. Bc4, no?

Here again white has two king moves (both of which leave white down a piece, and is worse than our KOTH), and one block with his tiny pawn.  However, that pawn block comes with a punch, because it is again attacking black's queen!  So after 1. Bc4 Qxc4+ 2. b3:

After this simple block by the simplest of pieces, the roles have again been reversed and now black has to deal with two threats!  The checkmate threat takes priority, and no matter what black tries the best he can do is go desperado and snatch a pawn and the g7 bishop for his queen.

This position demonstrates very clearly the power of blocking with a like-piece, and how you can turn a simple pawn block into a game-winning counterattack!  This position also shows the risks in counterattacking!  Looking at the original position, black should have calculated his move Qe6+ a bit longer.  It clearly would have been much safer for black to have just captured the g7 bishop instead of going for a some fancy counterattack/intermezzo!!

Finally, the last position demonstrates additional blocking options when the threat is one move away.  In this position you can expand the block concept to moves that "prepare to block", by either moving a piece into position to block once/if the threat is played, or by moving the king out of the way to allow a piece to block.

I'll leave this last one as a puzzle.  It is white to move:

5rk1/2p4p/Bpn1p3/p2PP1q1/3PP3/PP3p2/1BQ2P1r/2RR1K2 w - - 0 1

[HIGHLIGHT TO SEE ANSWER:  White's only defense is to move his king to allow the a6 bishop to block: 1. Ke1 Rh1+ 2. Bf1]

Calculating Forcing Moves: Defensive Idea 5 - Counterattack to DRAW (repetition)

In this series of posts we are looking at “counterattacking to DRAW”, which is using Equal or Greater Threats to force three types of drawn positions:

• Draw by stalemate;
• Material draw (equal material, fortresses, etc); and,
• Draw by repetition.

In the last two posts we looked at positions where there were clear threats on the board, and we created an EGT that allowed us to force drawn positions by stalemate and by reaching a drawn endgame.   In this post we’ll look at a position where the best move is to use a series of EGTs to force the opponent to repeat the position, resulting in a draw.

Black just played 1…Kxf4.  White to move.

2n5/3pB3/p3p3/2Q2n2/3p1kb1/1r6/q4PBK/3r4 w - - 0 1

Let's evaluate the position, and then find and prioritize all of black's threats.

Evaluation:  White is clearly losing. Black is up two rooks, a knight, and three pawns.   White is considering whether he should do the noble thing and resign.  The only thing going for white is his extreme lack of pieces and almost complete immobility…this immediately brings to mind stalemate themes.

Threats:  Black’s threats are many, but the fastest forced checkmate I can find is 2…Rh3+ 3. Bxh3 (only) Qxf2+ 4. Bg2 (only) Qg1#.

Let's look at the five defensive ideas to see what options white has to reply to the threat.

Idea 1 – do something to the attacking pieces (the g4 bishop, both rooks, and the queen).  We cannot capture, pin (absolute, given the mate threat), or deflect any of black’s attacking pieces.

Idea 2 – block the attacking pieces (the g4 bishop, both rooks, or the queen, from getting to h3, f2, or g1).  White has five blocks (2. Qc3, 2. Qc2, 2. Bf3, 2. Bg1, and 2. f3), but in all cases black simply captures with the queen or rook, which reinstates the same threat.  If the bishop leaves g2 (for 2. Bf3 and 2. Bg1), this simply allows a capture-check and a new forced mate (2…Qxf2+ 3. Bg2 Qg1#)

Idea 3 – move the piece being attacked (the white king).  The king has zero legal moves. Creating an escape square for the king by moving the bishop somewhere threatening (like say 2. Bd5) allows the same capture-check and a new forced mate mentioned in Idea 2 (2…Qxf2+ 3. Bg2 Qg1#).  Moving the bishop to f1 blocks the first rank, but still allows the new forced mate.

Idea 4 – reinforce/defend the attacked square or piece (the h3, f2, and g1 squares).  The are two moves that defend h3 (2. Qa3, and also 2. Qc3 that we looked at under Idea 2) but in both cases black simply captures the queen.  There are three moves that defend f2 (2. Bh3, 2. Qc2, and 2. Qxd4) but again black simply captures and checkmate is back on.  There are zero moves that defend g1 a second time.

Idea 5 – counterattack with an equal or greater threat (of checkmate).  Looking at the EGT chart from earlier we can see that against a checkmate threat, you can only counterattack with a check.  This is a good place to recall my earlier post on counting checks.  Instead of looking at every piece and then searching for each and every check, we can see that only the queen and dark-squared bishop can check the king, which equals a maximum of 14 checks because the bishop normally has 2 (unless one is off the board), and the queen has 12 when she is on the same color square as the target -- that is three checks in each of the four directions the queen can move.  (She only has ten checks when on the opposite color square, because there are only two on each diagonal instead of three.)  In this position the queen has two checks along the 5th rank (2. Qe5+ and 2. Qxf5+), two checks along the c-file (2. Qc7+ and 2. Qc1+), one check on the a3-f8 diagonal (2. Qd6+) and one check along the a7-g1 diagonal (2. Qxd4+).  The bishop can deliver both of its checks (2. Bg5+ and 2. Bd6+), for a grand total of eight checks.

This process has generated eight specific candidate moves, all of which are checks:

The next step is to calculate all eight of the candidate checks.  As I noted in earlier posts about counterattacks we do not know the outcome of the counterattack when we begin calculating, but in this case the position is so extremely bad for white that we can only accept extreme outcomes – a forced checkmate, or forced draw by stalemate or repetition.  We will not be able to capture enough material to reach an equal (or materially-drawn) position, and we won’t be able to construct a fortress.  Even if we could use checks to allow another defense against the checkmate, we’d still be losing.

How to pick which check to calculate first?  They are all forcing, but some are more forcing than the rest meaning they allow white fewer replies.  Quickly counting replies for each check, I see that two of the checks (2. Bg5+ and 2. Qe5+) only offer black one single reply, so we’ll start with those.  I actually do this “reply count” in my head as I’m counting checks to see which checks offer the fewest replies.  Let’s start with 2. Bg5+:

2…Kxg5 (only) and now white must keep delivering checks, hopefully to rid himself of all mobile pieces (the queen, pawn, and bishop) to force stalemate and we have 3. Qe7+ or 3. f4+.  There could be move order issues here so we’ll try both ways.  Let’s start with the queen check first:

3. Qe7+ Kf4 (if either knight captures the queen, 4. f4+ allows white to immobilize his pawn and self-pin his bishop -- stalemate) 4. Qg5+ Ke5 (4. Qd6+? Nxd6 avoids stalemate; if 4…Kxg5? 5. f4+, stalemate).  Here white has five queen checks and one pawn check.  Black cannot capture the queen if his king is on e5 or g5, since it allows f4+ (and stalemate), so the black king must move away from those squares before he can capture the queen.  White of course does not want to allow the black king to get away from those squares.

That eliminates three of white’s checks (all of the queen checks on the f-file), leaving three checks: 5. f4+, 5. Qg7+, and 5. Qe3+.  Since shedding the pawn is an important goal, and the two queen checks seem to allow the king to leave e5, let’s start with:

5. f4+ Kd6 (only) 6. Qe7+ (only check) Nfxe7, and now there is no stalemate because the pawn can move to f5 without a check.  Let’s try white’s two other checks at move 5:

5. Qg7+ Kd6 (5…Kf4 allows 6. Qg5+ leading to draw by repetition), and here white has five checks but since the black king is now not on e5 black can capture the queen.  This only allows white two checks -- one where black cannot capture the queen (6. Qf8+), and one where the capture would put the black king back on e5 (6. Qe5+).  After 6. Qf8+ Nce7 and now both of white’s checks allow black to capture.  That leaves 6. Qe5+ Ke7 (only) 7. Qc5+ (white’s four other checks allow black to capture) Ncd6, and white has no checks and black has avoided the stalemate.  That only leaves one other candidate check at move five:

5. Qe3+ Kd6 (capturing the queen allows the pawn check, and stalemate), and just like in the last variation, again white has five checks but since the black king is not on e5 black can capture the queen.  This only allows two checks -- one where black cannot capture the queen (6. Qf4+), and one where the capture would put the black king back on e5 (6. Qe5+).  We already know from above that 6. Qe5+ Ke7 allows black to avoid the stalemate, so we only need to calculate:  6. Qf4+ Ke7 (looks best; 6…e5?? 7. Qxe5+!; and 6...Kc5 looks good for black too, but white still has lots of check while after 6…Ke7 white very quickly runs out of safe checks) 7. Qg5+ (only safe check) Kf7!, and now white has no more checks.  White can capture the bishop, and perhaps a rook as well, but this is still completely won for black and white still has too much mobility to try for stalemate.

So all of white’s move 5 ideas failed to force checkmate or force a draw, so let’s back up a move and look at white’s other move 3 option, after 1…Kxf4 2. Bg5+ Kxg5 (only) 3. f4+:

3…Kh4! (threatens …Rh3#) 4. Qe7+ (only check) Nfxe7 5. f5 (only) Rh3#

After our first candidate move (2. Bg5+), white cannot force mate and cannot force a draw but since he has evaded checkmate so far and is in a position to capture some black pieces (in the variation after 5. Qe3+), we’ll make this our KOTH.

Only seven more checks to go!!  Deep breath…and moving on to the next most forcing check:

1…Kxf4 2. Qe5+ Kxe5 (only), and here white has three checks but one of them is the most forcing (allowing only one reply), 3. f4+ Kxf4 (only), and we are one step closer to stalemate.  We only need to get rid of our overly-mobile bishop using checks, of which we have two:

If 5. Bd6+ Ke3 and white will soon run out of checks, and will lose.  That leaves us with one last check in the variation:

If 5. Bg5+ Ke5 (forced, 5…Kxg5? is stalemate) 6. Bf6+ Kd6 (forced, 6…Kxd6? is stalemate, and 6…Ke5 repeats) 7. Be7+ Kc7, white just needs to keep checking and now allow the black king to get to c5 or b6, so 8. Bd8+ Kb8 9. Bc7+ Ka7 (only) 10. Bb6+! Kb8 (not 10. Bb8+? Kb6!, and black can get to a light square and escape the checks) 11. Kb8 Bc7+, and although we can’t force the black king to capture our last mobile piece which would force stalemate, repeating the position is black’s only way to not capture the bishop, which is good enough for the draw!

Normally we would note the drawing option, and then continue calculating the other six checks.  But since a draw is really all we can hope for from the starting position, there is no need to keep calculating!  Here is our final chart:

Conclusion:  So this process has shown us that white has several candidate moves to consider in the initial position, and if we follow the path of the most forcing moves first we are able to find the forced draw!  Black has no say in the matter, and his only choice is whether to allow draw by stalemate or repetition!

This is the process you should be able to do mentally:  prioritize the threats, use the five defensive ideas to search for specific candidate moves, calculate each one completely, and then pick the best variation based on the final evaluation.

In the next post we will look at positions where we use EGTs to rearrange our pieces to allow one of the basic defensive ideas (from Idea 1-4).