Wednesday, June 17, 2015

Chess960: Playing Komodo-9 64bit

I decided to play Komodo-9 in a game of Chess960 because the consensus is that it plays natural human looking moves, which might be a nice way to practice Chess960 openings.

So I played Komodo-9 on SP456 - a nice easy number to remember!

Here is the situation at move 2:

SP456 White (Komodo-9) to play move 2

My first move as black was a very natural move that takes good control of the center. Komodo's first move f4 surprised me a little. I'm not sure if it is a good idea to commit to weakening the light squares on the kingside so early when there are better moves. f4 does threatens f5 at some point which would kick black's knight if I planted it on e6. However that is not a threat. I would instead play Nc6/Bd7 which opens up some nice lines on the light squares for my bishop against white's kingside. 

But now I really got a shock. Komodo-9 decides to play Qf2?! This cannot be a good move. There is no point playing out the queen so early while also blocking the dark square bishop in the process. Trying to defend f4/f5 so soon seems to be silly.

So I analysed what my other engine Stockfish thought of Komodo's move. Here is the result:

Stockfish at depth 22 thinks that after 2.Qf2?! Black should play ...Nd6 with a slightly better score -0.16. On the other hand, Komodo-9 at depth 18 thinks that black should play ...Nd6 but that white is slightly better at 0.14.

So after 2.Qf2?! we can see that Komodo-9 has issues playing Chess960 openings. Firstly, it is a slower engine than Stockfish when it comes to achieving the same depth. Stockfish got to depth 22 really quickly. Perhaps the depth of the calculation is really important in the Chess960 opening which favours Stockfish.

But Komodo's issue is not just depth, but also evaluation. There is no way in hell you can tell me that after 2.Qf2?! white is a bit better? Stockfish's evaluation of the position seems to me to be about right if not even a bit too conservative in it's favouring of black after 2.Qf2?! Nd6.

So I thought I would take a look at the CCRL 24-hour-a-day computer engine competition. In standard Chess Komodo appears to have the current lead. But in Chess960 the story is different. Stockfish is still the leader with a 50 point ELO rating higher than Komodo.

Well there you go. A little bit of engine trivia for you.

Enjoy 960

Tuesday, June 2, 2015

Chess960: Puzzle no.16

Dear followers of this blog, enjoy this unusual puzzle. It requires an understanding of what a pawn island in Chess is. For more information see a definition Pawn islands (wiki). Often in Chess960 openings we try to avoid creating long lasting pawn islands because the isolated pawn or pawns are a long term target of attack for our opponent to exploit. There are exceptions of course!

In this position, both white and black have three pawn islands each.

White has three pawn islands (a-e),(f),(g-h).
Black has three pawn islands, (a-f), (g), (h).

Here is the puzzle,  the answer is surprising!

SP455 move 2 white to play:
If white captures the g-pawn, who will have the
greatest number of pawn islands before move 7?
White, black or equal number?
Solution given bottom left hand corner

Answer: White!
2. fxg5      white has three pawn islands, black two.
2. ...h6     no change, white=3, black=2.
3. gxh6 Qxh6 white=2, black=1
4. h3   Be5! no change
5. g4   Bh2  no change
6. Rg2  Qxh3 white=2, black=1

White has more pawn islands than black. If instead white tries 5.Nbc3 or any other move, white still has one extra pawn island than black.