Season 16 superfinal games 81-90

After 90 games Stockfish leads 12-4 with 74 draws. The last 10 games were all draws, Stockfish continues to lead with a gap of 8 points.

There were almost no exchanges after the start of game 81, Stockfish's eval was 0 and AllieStein's eval was under 1. In a series of exchanges Stockfish traded RB for Q and then it started to chase the white king with checks. AllieStein gave back the material and the game reached a knight ending. The engines continued to play, the game ended in a tablebase draw. In game 82 the king side opened early and Stockfish preferred to castle long. AllieStein's eval turned negative, there was a long period of mainly shuffling and then a long series of exchanges that left a BNN vs BNN position. Both evals came down, the engines played until AllieStein's eval was low enough for the draw rule.

Games 83-84 started with a 20-ply book sequence in the Sicilian Najdorf opening, Adams attack variation. In game 83 the engines castled in opposite directions, Stockfish's eval was 0 almost from the start. Stockfish gave a rook for a knight and pawns, opening the queen side. AllieStein moved its rook and to the 7th rank, then its queen moved forward. This left the white king exposed, Stockfish started giving checks with its queen. Eventually the game ended in a check repetition. In game 84 the engines first exchanged pawns and pieces in the center and then castled in opposite directions. Stockfish gave a pawn and then the engines exchanged all rooks, only QB vs QB remained on move 33. The engines exchanged a few pawns and pushed passers forward, then Stockfish forced a repetition draw.

AllieStein started game 85 with an eval over 1. The engines gradually exchanged pieces and pawns, on move 33 only QBB vs QBB remained with pawns only on the king side. After a long shuffle the engines exchanged down to a same color bishop ending. AllieStein was a pawn up and it wouldn't lower its eval. Pawn moves kept the game going until a 50-move draw on move 193. In game 86 queens were exchanged early, the engines opened the queen side and removed all knights. Stockfish was a pawn up with an advanced passer on the queen side, AllieStein's bishops controlled the center and it moved a rook to the 2nd rank. AllieStein captured the passer, Stockfish gave a rook for a bishop and the game reached a RBB vs RRB position with white two pawns up and evals at 0. The black king was exposed and AllieStein started giving checks. The game should have ended by the draw rule, in the end it was a draw by repetition.

Game 87 was a miniature that ended in a repetition draw on move 17. In game 88 all the pawns were on the board and the engines played behind their pawn lines. The engines started to shuffle after the first pawn exchange, Stockfish avoided a 50-move draw and opened the queen side. The engines exchanged pieces until only QR vs QB were left with black a pawn up, the game was adjudicated by the draw rule.

Queens were off early in game 89, forcing the black king to move. Alliestein captured a pawn and opened the king side, it kept its king uncastled as well. The game reached a RRN vs RRN position on move 35, AllieStein's eval came slowly down. The engines continued to exchange pieces and pawns, the game ended in a tablebase draw. In game 90 there were several early exchanges that opened the queen side, Stockfish went two pawns up yet evals were close to 0. Queens were exchanged, AllieStein's pieces were more developed and it pushed pawns on the queen side while Stockfish improved its position. After trading all the queen side pawns Stockfish pushed pawns in the center. There was a long series of exchanges and only N vs B remained with equal material and pawns only on the king side. The game was adjudicated when evals were low enough for the draw rule.