534 ( +1 | -1 ) how to mate...Ok, some explanations (because I feel that the given site doesn'T really explain the idea)... First, the mating process consists of three steps: 1) centralize your king and pieces 2) drive his king to the boarder 3) mate him in the corner that your bishop controls.
Now, take out a board and set up pieces (I just go through one of my mates to show you the ideas, then you should simply play this a dozen times against a computer, because it's essentially always the same). First idea is to realize that your knight and bishop can form a kind of barrier: imagine Bc2 and Ne2. Now, you control the squares a4, b3, c3, d3 and d4. Were his king on c4, he couldn't come closer to your pieces. Imagine your king now coming from the side (Kd4, maybe), and his king would have to go back... One further general remark: The key to this mate is not constant threats but confinement. ***Don't think primarily about pushing his king, but more about cutting off his escape route!***
Now, here's my game...
Start: wt: Kc2, Nb7, Bg7; bl: Kg4 1. Kd3 (remember the first step - centralize your king and your forces) Kf3 (of course he knows that doom awaits at the rim - therefore he tries to centralize as well) 2. Nd6 Kf2 (after ... Kf4 Kd4, he has to go to the rim anyway. But he's struggeling to keep away from it as long as possible) 3. Ke4 Kg2 4. Bd4 Kg3 (trying to stay off the back rank. If he had moved there, Kf3 would have kept him there...) 5. Be3 Kg2 6. Nf5 Kh2 (finally!!!) 7. Kf3 ------------- Ok, this was only the prelude. This is the first position you have to memorize. Of course, it can occur on all four corners. The basic position is always characterized by your king on f3, c3, c6, or f6 (depending on what bishop you have). His king is driven into the corner. And there he will stay unless you drive him towards the corner where you can mate him. The next moves are basically forced and should be simply learned by heart. The first is to bring the knight in... ------------- 7. ... Kh3 8. Ng3
This is the position you're aiming at. Doesn't matter if it takes a couple of knight moves to get to g3 (or, if he goes the other way - h1-g1 etc., Nf2 - it doesnt matter). As you can see, his king can't escape: g2,g3,g4 are covered by the king, h5 and h1 by the knight and g5 and g1 by the bishop. Even if the bishop were not on e3, you would always have the time to keep him in by moving the bishop towards the right diagonal to cut off his escape route. 8. ... Kh2 (of course, staying away from the corner where he can be mated!) 9. Bf2 (exclam! This move is important. Remember my remark about confinement above? This is what you're doing right now: This one move is simply "loosing" a tempo such that he has to move again... 9. ... Kh3 (only move 10. Bg1 (taking away that square - now the king has no choice but to move up...) Kh4 ------- Ok. So far, so good. Now comes a series of moves that at first sight strike you as completely counter intuitive. You simply HAVE to learn those by heart. As mating with k+b takes up to 28 moves (especially if you let his king slip now), you'll likely not make it within 50 moves and the game would be drawn. So you HAVE to know those moves. -------- 11. Ne4 Kh5 (don't worry why he's going up voluntarily - we'll come back to that) 12. Kf4 Kg6 13. Ng5 Those are the magic moves you simply have to make! Once you've reached this position, it's not that hard anymore, because the above confinement-idea comes in again. 13. ... Kg7 (now, it _looks_ like he's getting out, doesn't it?) 14. Bc5!! Taking away the escape route! No checks, just keep him under control! 14. ... Kf6 15. Bf8 (See how bishop and knight take away every square he would love to move to?) Kg6 16. Be7 --------- That was the next maneuver you have to know - though the moves are not completely forced (he could go to f6 right away on move 13, for example), But still, that bishop maneuver, cutting off his escape is the same. It's the only move, and it's somewhat hard to find if you are looking for a direct threat but if you are thinking "how do I cut off all his exits?" it's not that hard anymore. The next bishop moves were (similar to that Bf2 move in the beginning) kind of "waiting moves". The idea is to drive the king off the dark squares to be able to control those. Now, you can see that Bishop and knight form a barrier from f8 to f6! That's important. ------- 16. ... Kh5 (back to trying to stay away from the mating corner) 17. Nf3 The last difficult maneuver. The idea is twofold: First, it frees the diagonal, forcing the king up, and secondly, it aims to control f7 again by going to e5. 17. ... Kg6 (hoping to escape via f7!) 18. Ne5+ (denying f7!) Kh5 19. Kg3 (now you're simply herding the king into the corner.) Kh6 20. Kg4 Kg7 (but no exit point for him!) 21. Kg5 Kh7 (almost there. As white mates with the king on g6 or f7, black tries to deny that square as long as possible. --------- Here comes the last little trick to know. Now, you have to take away the last few squares. Again, it's confinement rather than direct treats. 22. Bf8 Kg8 (now, he has only three squares left) 23. Bh6 Kh8 24. Kg6 (ok, the king is set - that's his mating square. Had he moved Kg7 on the previous move, you'd have simply "lost" a move by playing Kh6) 24. ... Kg8 25. Ng4 Kh8 It's important now to not stalemate him by playing Nf6!! So, now: 26. Bg7+ Kg8 27. Nf6# :))
--------------------------------------- Back to move 11 where I said that you shouldn't worry that the king goes towards the corner of mate rather than continuing to try to stay away from it. The reason is simple... 11. Ne4 Kh3 12. Ng5+ Kh4 13. Kf4 Kh5 14. Kf5 Kh4 15. Bh2 Kh5
All those moves were forced. And if you look at the position of the pieces relative to each other, it's exactly the same position you had after 10. Bg1! The only exception is, that now, the king is a) farther up the board b) even without that little chance of outrunning you. Therefore, it's not the best defence.