The engines castled in opposite directions in game 81. Stockfish's eval was around 1 after the start, it pushed pawns on the king side with support from its rooks. The king side opened and Leela hid its king behind a white pawn, then on move 26 Stockfish's eval jumped over 7 with no warning.
Leela wasn't expecting Stockfish's 28th move, white abandoned two minor pieces but the black king was in a mating net. Leela had to exchange RB for Q but it was too late. Its king was still under threat and Stockfish controlled the 7th rank. The black pawns started to fall.
Stockfish captured the knight and was 4 pawns up when the game was adjudicated a few moves later.
In game 82 the pawns in the center and on the king side locked early. There was one open file on the queen side, all the pieces remained on the board with the first piece exchange on move 23. By then Leela's eval was over 4, though it wasn't clear why. After exchanging a pair of rooks Leela took over the open file, its eval over 6.
Stockfish had very little room to move. It refused to take the rook on c6 since this would create an advanced white passer. The engines continued to shuffle, Stockfish was almost paralyzed and Leela was patient and arranged its pieces. It put a rook on the back rank and waited for an opportunity. On move 61 Stockfish abandoned its b pawn.
A few moves later Leela captured the b pawn, and then captured a bishop. Stockfish's admitted defeat and the game was adjudicated. There were two white wins in this opening.
Games 83-84 started with a 28-ply book in the Sicilian Dragon, Yugoslav Attack variation. White castled long and black castled short. In game 83 Stockfish pushed pawns on the king side and it managed to open a file. Evals came down as the engines exchanged pieces, reaching a same color bishop ending on move 40. Leela thought it had a small advantage and the game continued for 20 more moves and reached a tablebase draw. In game 84 Leela went a pawn up, exchanges cleared the black pawns on the queen side. Leela had two connected passers on the queen side, Stockfish had a passer in the center and its eval remained low. On move 28 Leela gave a rook for a bishop, its eval over 1.5. The black king was a little exposed, Stockfish was active on the queen side and this prevented an attack on its king. On move 45 Leela gave another rook for a bishop, only QBB vs QRR remained with Leela two pawns up. The bishop pair was very strong, Leela could get some of the material back but chose to wait. After exchanging queens a white passer reached the 7th rank, Stockfish lost a rook to stop it. Both engines queened in the BB vs R ending, it cost Leela a bishop. The game reached a tablebase draw in a QB vs QR position on move 107.
Queens were off early in game 85, evals started around 1 and slowly came down. Stockfish went up a pawn and created a queen side passer, the game reached a RRB vs RRB position on move 27. Evals came down to 0, Leela's eval went slightly negative when it regained the pawn. The engines reduced to a bishop ending on move 47, Leela went up a pawn and continued playing until reaching a tablebase draw on move 96.
In game 86 the action was on the queen side. Leela pushed pawns forward, after exchanging a pair of rooks the engines captured most of the pawns on the queen side, leaving one white passer. Leela's eval was around 1.5 as the engines continued to exchange pieces until reaching an opposite color bishop ending on move 40. Instead of being a drawish ending as usual, without warning Stockfish's eval jumped over 7 as it saw the loss coming.
The black bishop had to keep an eye on the a7 square, the black d pawn could not be protected. Leela created a passer on the king side and protected it with its bishop, now it saw the win as well. Stockfish was going to lose the bishop for one of these passers eventually and the game was adjudicated quickly.
There was one piece exchange early in game 87, all pawns remained on the board. Leela's king walked to the queen side, Stockfish castled short and then changed its mind and its king walked back to the center. Leela's eval turned negative as the engines shuffled, Stockfish pushed a pawn to a6. The first pawn was captured on move 45, Leela took the a6 pawn and went a pawn up, exposing the queen side to the white pieces. Leela's eval turned positive again and Stockfish's eval started to climb, it opened the king side and created an advanced passer in the center. When the passer reached the 7th rank Stockfish's eval was over 4, Leela was still feeling secure with an eval under 1.
The pin and attack on the a6 pawn together with the dangerous d7 pawn were too much to defend, as Leela soon realized. It gave Q for RB and its eval jumped over 8, the game was adjudicated before Stockfish won more material.
In game 88 there was one pawn exchange on move 16 and all the pieces remained on the board. Both engines castled short, Stockfish's eval was low and Leela's eval was around 1. On move 32 the engines started a series of exchanges, Leela's eval jumped when Stockfish gave a rook for a bishop. The game reached a RRN vs RNN position on move 39.
Evals continued to increase as Leela moved its pieces patiently. It took 10 moves for Leela to exchange knights and another 10 moves to capture a pawn. Leela's eval was over 10 by then.
The rook on h4 was trapped but not for long. The white king moved to the center, Stockfish had to move its pieces and the white rook could get out safely. Stockfish avoided exchanging rooks and it defended as long as it could. Eventually Leela moves a rook behind the black pawns and used the other rook to keep black king far on the other side. The game was adjudicated on move 99. Two white wins in this opening.
Games 89-90 started with a 19-ply book in the Benoni Defense. Evals were around 1 at the start of game 89. The first piece exchange was on move 24, in a series of exchanges all the queen side pawns were gone, Leela gave a rook for a bishop and the game reduced to a RRN vs RBN position on move 34. The knights were exchanged, evals came down and the engines started to shuffle. Leela's eval turned negative, all pawns were gone except for two black pawns. Leela continued playing, the game was finally adjudicated on move 180 with the 50-move draw counter almost at 0. In game 90 there were again only a few exchanges from the start. Leela controlled an open file on the queen side, Stockfish gave a rook for a bishop and pawn and Leela's eval jumped over 3. After exchanging queens the game reduced to a RRB vs RBN position on move 40. The white rooks were strong but the bishop was trapped on the king side. Leela went a pawn up and its eval close to 10 but it couldn't find a way to close the game. The engines shuffled, then exchanged rooks, Stockfish got a pawn back and the engines shuffled some more. The white bishop stayed trapped and Leela's eval slowly came down. On move 155 Leela finally gave its bishop up for a pawn and the game reached a drawn 7-man R vs BN position. The game was adjudicated on move 211. Was that a narrow escape for Stockfish? Or was it a bad evaluation by Leela?
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