Originally posted by Sophy
Game 5725206
When you play openings such as the Pirc, King's Indian Defence, etc., understanding the role of Black's fianchetto bishop is very important. It usually plays a key role in the subsequent middlegame.
- watch for ideas by White to swap this bishop off; White's own dark squared bishop is often used to oppose/attack Black's bishop and initiate a swap
- be aware of opportunities to open the a1/h8 diagonal
- the mobility of Black's e and f pawns often allow Black to push these pawns forward, gaining space and/or opening the diagonal for the bishop
- you often want to play on the side that you're strongest on (e.g. compare the number of pawns opposing each other). For Black here, it is on the kigside. White may try to counter on the queenside.
With these ideas in mind, consider the position prior to 12...Bd7?!.
12...Nxe3 is better here. Why...
- if Black's f-pawn is ever going to f5, the knight on f5 needs to make up its mind what it's doing. Since it just came from e7, I don't see any great squares for it to go to. So swapping off this knight is fine for Black.
- Black's fianchetto bishop is happy than his opposing piece in the White camp is gone. If Black's bishop gets to open fire on the long diagonal, the main "antidote" is gone
- Black may plan to "play on the dark squares". Nxe3 forces White to reply fxe3, putting a weak pawn on e3 (a dark square). Then, the Black queen is ready to go to b6, hitting e3 and b2. Black's bishop may also go to h6 to hit e3. Also, if Black succeeds in playing f5 - and maybe e4 too - White's lone bishop is not a happy piece. Such is the effect of White not maintaining his dark squared bishop in this position
So, 12...Nxe3, fxe3, Nxe4, Nxe4, f5, Nc3, Qb6 is much better for Black.
17...a6?!
Again, f5 is what the position requires.
20...Rb8?!
This is an interesting move because superficially it looks fine. But digging just a little deeper, we see that if White then play Rxf8+, Black must response Rxf8. Notice, it's almost as if the move Rb8 didn't happen and Black skipped a move. If you do see such a line, ask yourself if you can play an intermediate move that can't be cancelled out. If Black had played, e.g., 20...Bh6, then after Rxf8+, Rxf8 we have the same position as the game accept that Black's bishop is on h6 and that's a useful move to get in while anticipating White's Rxf8+
22.Bb5 resigns ??
Why resign? I see that Black's bishop on d7 can be protected by the rook, so maybe you thought that White's a-pawn had an unstoppable path to promotion?! Maybe the b pawn too?! If so, then even without analysing anything, the position still warrants your opponent to "show it in practice". And under objective analysis, I think Black can stop White's plan (e.g. Rd8, a4, Bh6, etc).