Ten Puzzles Easy to Hard

If you regularly read my blogs and like having puzzles to solve, I think you may enjoy this post...

Ten puzzles follow below. They start off easy, but ramp up in difficulty as you move forward.

Test your wits and see how far you can get! I will post the answers at the end of March.

1

White to move and mate in 1.

2

White to move and win.

3

Black to move and win.

4

With best play, does black win or is this position a draw? Assume black to move.

5

What is the fewest number of moves it takes for white to force mate?

6

Suppose from the starting position, white can make eight pawn moves in a row, but they all have to be with the SAME pawn. You must still keep moving the "pawn" even after you've promoted it. Given these constraints, find the only way for white to deliver mate on the eighth move without playing a single check until the final checkmate.

7

Find the best continuation for black.

8

Black to move and win.

9

White to move and win.

10

White to move and mate in three.

Prophylaxis: Stop your Opponent's Plans

Last time I explained what prophylaxis is; now I'll show an example where I walk through my actual thought process to show how you can use this kind of thinking in a real game with strong effect.

The position below is from a game I played against NM Daniel Johnston in 2018 (I was white).

Ok, so what's going on here? The position looks about equal - black has the bishop pair but in return has a worse pawn structure and a passive rook, so ultimately these things balance out somewhat.

From the diagram, it was black to move, and Daniel played 20. ... e6 (D)

Now, it's my turn. So naturally I have some short-term goals and stuff that I would like to do - for example I want to centralize my king and maybe also get my knight to a more active square. But it's important to not just quickly play something like Ne5 or Kf1 here, because maybe black has an idea of his own behind the move ...e6 that we should consider and take steps against.

Fine, so before making a move, let's ask ourselves, "why did he play ...e6?" Well, at first glance maybe it's not so obvious, but you can see that it opens up the a3-f8 diagonal for his dark squared bishop - maybe he wants to play ...Bf8 and attack my rook? Ok, so what - if he does that then I'll just move it away; no harm done. But hold on a second, what if after that he then breaks out with c6-c5? Then he gets some activity - maybe in the future he'd be able to play cxd4 (although not immediately because of the pin) or even c5-c4 to make a passed pawn. I decided that I didn't want those things to happen, so I found a way to "stop" ...Bf8 from chasing my rook away. What move did I play?

The move I came up with was 21.Bd6! Now, if black still wants to play ...Bf8, I'll just trade the bishops and leave my dominating rook on c5.

While my move seems sort of random if you're not thinking about black's plans, once you see what black wants to do you can understand the logic behind Bd6.

Black continued with 21. ... Bd3 (D)

Notice how Daniel is also hindering me from executing one of my own plans - now my king has a hard time getting out.

Ok, so what do we do now? Just play a quick move like Ne5 to chase the bishop away? No, not so fast. We should do the same thing as before and try to figure out if there is some other idea behind ...Bd3 that we can stop. It turns out that there is.

If the bishop could move again, where might it go? There's a few options but the one I was worried about was b5. Imagine that bishop sitting on b5 - it defends both c6 and a6 and although in theory I could kick it out with a2-a4, you'll see that it's actually not so easy to come up with an efficient way to do that. Once c6 and a6 are anchored, his rook will be free to roam around and do stuff. I decided I didn't want any of that to happen, so I stopped ...Bb5 with 22.a4!

Daniel responded with 22. ... f6 (D)

Alright, so once again we should ask ourselves, "what's his plan with ...f6?" Do we need to take any preventative measures?

Well, the only things I could think of is that maybe black wants either ...e6-e5 or ...g6-g5 or simply wants to activate his king via f7 while keeping my knight from advancing.

I have good control over e5, so I shouldn't be worried about that pawn break. I wasn't worried about g6-g5 either - if black wants to waste several moves to start a pawn storm, then he can go ahead. We're in an endgame and I'm not going to get mated; those pawns will be weak later.

So ultimately, I decided that I don't have to take any preventative measures - this means I can finally start doing my own stuff.

From the diagram, I continued with 23.Nd2 to relocate my knight; my plan is f3-e4 and Kf2. After 23. ... Bf8 24.Bxf8 Kxf8 (D) we reach the following position:

We've only gone five moves from the initial position but look how much things have improved for me - we have a classic good knight vs. bad bishop, black's rook is still passive, and even his bishop is in danger of getting trapped if he's not careful. I can continue with things like f3-e4, Kf2-e3, and Ra5 & Nb3-c5 to target the a6 pawn. We've gone from rough equality to white having a pretty serious advantage.

However, it could have been a very different story if I did nothing to stop ...Bf8 and ...c5 earlier, or if black's bishop became outposted on b5 with my pawn still on a2. If either of those things had happened, I probably would only have a small plus, if anything at all.

From here the game becomes less about prophylaxis and more about how to convert an advantage, so I'll just briefly go through the rest.

From the diagram we continued 25.Rc3 Be2 25. ... Bf5? 26.e4 Bg4 27.f3 Bh5 28.g4 and the bishop is lost. 26.Ne4 Ke7 27.f3 (D)

Intending Kg1-f2 to start rounding up the bishop. Notice how black's rook is for now unable to go to the b-file because it has to defend c6.

27. ... Bd1 28.Rc4 keeping the bishop in a cage. I accomplish nothing after 28.Nc5? because it allows 28. ... Rb8! when black's rook suddenly becomes very active after 29.Nxa6 Rb1! 28. ... Rc7?? (D)

The decisive mistake.

29.Nc5 Had the rook been on c8, black could play ...Rb8 and get counterplay, but unfortunately for him b7 is covered now - there's nothing to be done about Rc1, eventually trapping the bishop. 29. ... Rc8 30.Rc1 1-0 On 30. ... Be2 there is 31.Kf2

This detailed example should illustrate the importance of being aware of your opponent's ideas and taking measures to stop them if they become threatening. A good player will have his own plans, but a master player also constantly thinks about his opponent's plans and actively tries to hinder them.

Prophylaxis

What does prophylaxis mean in chess? I think a good chunk of club players might not be fully aware about how important the concept is over the board, and even some players who are aware can forget about it completely during their own games. In reality, prophylaxis is not an advanced idea, but it does requires a certain mindset to be used effectively.

In medicine, "prophylaxis" specifically means some kind of treatment that is designed to prevent a disease from happening. For example, you get a flu shot as prophylaxis against the flu virus. Of course, it's not a sure bet that you'll actually get the flu if you neglect the shot, but if you do get the vaccine you're significantly less likely to get sick.

Over the chessboard, it's exactly the same idea, just a little more abstract. Prophylaxis in chess is anything that prevents your opponent from doing something that would be bad for you in the future. Now, that's a very broad definition, but I'll illustrate with a basic example that I think many of you would be familiar with:

In this position, most experienced players with white would probably play a move like h2-h3 to make luft before doing anything else. But why? After all, black isn't even threatening back rank mate right now. Why would we play h2-h3 like this if there's no threat?

This highlights the key difference between "prophylaxis" and "defense". The point of h2-h3 here isn't to defend against an immediate threat of checkmate; rather, it's designed to prophylactically stop all future back rank mates because we'll always have an escape square on h2.

Of course, I can't say for sure that you will get back ranked if you neglect such a move, but you'd definitely be at a higher risk - for example, here's how things could go horribly wrong if you don't make luft: 1.Rd1? Qb2! 2.Qxb2 Rxd1#. That would be painful, but it's completely avoidable if you had simply played h2-h3 earlier.

I'll show one more example that you might commonly see in practice.

We have a pretty standard Sicilian position, with white to move. What do you think is the most common move played by grandmasters here? You might think that it would be something to continue development - perhaps 9.Be3 or 9.Qe2, but it's actually 9.Kh1.

To someone unfamiliar with prophylaxis, this may seem like a somewhat bizarre move - after all, what does that king have to do with anything? Well, imagine that later black plays something like Qc7-b6 and then even d6-d5 and Bf8-c5. Suddenly you can see that the Nd4 would be in a dangerous pin against the king on g1, and we'd probably have to do some uncomfortable things to defend and escape. By playing 9.Kh1, white prophylactically avoids all that by stepping away from the pin before it even exists.

With those examples in mind, we can generalize our definition of prophylaxis as just any move that stops a good idea our opponent might have. If our opponent has the idea of playing for back rank mate, we stop it before it even becomes a threat. If our opponent has an idea of creating a pin against one of our pieces, we make some move to evade that before it even happens.

We can keep applying this to literally anything else - say you notice your opponent wants to maneuver a knight to a strong outpost; you could be prophylactic and stop that. Or suppose you have two undefended pieces and you think your opponent might try to fork them later; you could be prophylactic by moving one of them back to safety.

This leads us to the formula for thinking prophylactically - you have to ask yourself what your opponent wants to do. Put yourself in his/her shoes and try to figure out what their ideas are, and then stop them before they actually get a chance to happen over the board. I guarantee you this is something that every single grandmaster in the world does both regularly and effectively.

Have you ever played in a simul against a strong player and been sitting at your board, trying to guess what their next move will be? Perhaps you spend several minutes looking at all the obvious moves, and you come up with your own prepared responses to them. Then the master/IM/GM comes around to you, looks at the position for a few seconds, and to your surprise plays something completely innocuous with no apparent purpose. It's a good bet that move had prophylactic intentions. There was some tactical idea they were worried about in the future, so they simply move away from it long before it could even become a real threat.

I know this because I do this when giving simuls myself! I'm only human; I simply don't have the time or energy to calculate lots of variations on every single board, so I make things easier for myself by preventing the tactics from being able to happen in the first place. I use prophylaxis now so that I won't have to defend later. Only when my position is secure enough do I go about executing my own plans to actually try and win.

This brings us to the last point, which is that the key to gradually improving your position is prophylaxis. Next time I'll show some practical examples from real games.

Game of the Month: January 2019

In this game of the month for January 2019, we will see how a rash positional decision early in the opening can have a lasting impact throughout the game.

Kehoe, Webster (2030) - Campbell, David (2052)
CCCR Wednesdays
1/2/2019

1.e4 c5 2.Nc3 Nc6 3.f4 g6 4.Nf3 Bg7 5.Bb5 (D)

This type of Closed Sicilian with an early f2-f4 by white is typically known as the Grand Prix attack. Sometimes white chooses a setup with g2-g3 and Bf1-g2, but with 5.Bb5 Webster signals his intention to give up the bishop pair to permanently damage black's pawn structure.

5. ... a6!?

It is widely considered here that 5. ... Nd4! is the strongest response for black. The point is simple: we avoid any Bxc6 ideas and threaten to take the bishop anyway "for free". After the most common continuation 6.0-0 (White has also tried 6.Nxd4!? cxd4 but this gives black a strong cramping pawn in the center) 6. ... Nxb5 7.Nxb5 black simply has the bishop pair and it's not immediately obvious where the compensation is. Typically white doesn't accomplish much in those positions.

With his last move black daringly declares his opponent's idea to be so worthless that he's even willing to waste a tempo to force him to execute it! If not 5. ... Nd4, I would have at the very least preferred 5. ... d6, which contributes to development and influences the center.

6.Bxc6 bxc6 7.0-0 (D)

7. ... d5?

Although it looks natural to expand into the center like this, in reality this hasty advance is a serious mistake. The issue is that if white ever starts attacking c5, there's no way black can support it with a pawn anymore - he will either have to resort to painfully passive contortions to hold on to it or just accept its loss. For this reason the restrained 7. ... d6 was correct.

8.d3!?

A viable alternative was 8.e5! to close down the Bg7. This also would avoid a small escape that black could have taken on the next move.

8. ... e6

Black will be worse off no matter what, but I think the best shot is to try the endgame after 8. ... Bxc3 9.bxc3 dxe4 10.dxe4 Qxd1 11.Rxd1 Nf6 - the opposite colored bishops offer some drawing chances and at least white's structure is damaged too.

9.Qe1 Ne7 10.Qf2 (D)

It should be clear now that black is struggling to defend c5.

10. ... d4

Unfortunately there's not much else to suggest. 10. ... Qa5 runs into the unpleasant 11.Bd2, creating the threat of Nc3-xd5. Although we're only ten moves into the game, white is already completely dominating, all because of the weak c5 square. It is instructive to see the rest of the execution:

11.Na4 c4 Desperation. If 11. ... Qa5, then 12.b3 and 13.Ba3 will win the pawn anyway. 12.dxc4 Qa5 13.b3

Unfortunately there's no way black can take advantage of the exposed long diagonal. 13. ... d3 can even be met by the flashy 14.cxd3! Bxa1 15.Bd2 and 16.Rxa1 with dominating compensation for the exchange.

13. ... 0-0 14.Ba3 Re8 15.Rad1 Bd7 16.Bc5 Even though there's no pawn there anymore, it's still all about the c5 square! 16. ... Nc8 17.Nxd4 Bf8 18.Nf3 Qc7 19.Ne5 Rd8 20.Bxf8 Kxf8 21.Qh4 Kg8 22.c5 Rb8 23.Qf6 1-0

This is a good example of how just one or two hasty decisions in the opening can have a disastrous effect on the rest of the game. After 7. ... d5, white played almost flawlessly to realize his advantage.