Season 26 league 1

Final Standings

Berserk and Seer advance to the premier division. There were 5 engines leading after RR2: Seer, Caissa, Berserk, Obsidian and rofChade. Within this group Berserk drew all games while the other 4 each had one game pair win and one loss. In RR3 rofChade was dropped after losing to Caissa, Arasan and Clover, though it also beat Obsidian. Berserk led by a small margin at that stage after beating Caissa. In RR4 Berserk took over after 5/6 wins as white and one win as black. The other 3 leaders were close to each other, Caissa and Seer drew games as white against lower ranking engines 5 times. In the end all three had the same score, Seer had the advantage in the 3-way tiebreak with a game pair win against Caissa and draws against Obsidian.

Berserk completed the journey from the entrance league to the premier division, though it is not clear yet if it can avoid relegation back to league 1. It was 4th in the premier division of season 24. Obsidian also started at the entrance league and was close to joining Berserk.

The top 5 engines beat the bottom 7 in 41/70 game pairs, rofChade lost two. Clover crashed on time 4 times, strangely all these crashes were in RR2. In 3 cases it was close to losing, once it was in a drawn position.

The two qualifiers will play in the premier division together with Stockfish, Leela, KomodoDragon, RubiChess, Ethereal, Stoofvlees, all played in the premier division of season 25. This season the premier division will be a 4DRR event, without a playoff this season.

Interesting games

game 9, Caissa - rofChade: The engines opened the e file and gradually exchanged pieces, Caissa created a passer on the king side and the game reached a RN vs RN position. rofChade lost two pawns and created a passer on the queen side, while Caissa had a second passer in the center. The white king moved forward and rofChade lost its passer, it lost more material and Caissa queened, followed by mate.

game 17, Igel - Caissa: The center was blocked, the engines exchanged a few minor pieces. Igel placed a protected bishop on d6 and the opened the h file. The white king moved forward and the engines exchanged all rooks, the game reached a QBN vs QNN position. The black king walked to the queen side, Igel gave a knight for two pawns and created connected passers in the center. Caissa lost a knight for one passer, then it lost more material and was mated.

game 23, Revenge - Clover: Revenge pushed pawns on the king side and castled long, there were only a few exchanges after the start and the engines mostly shuffled. On move 39 Revenge captured a pawn and created a passer on the queen side, on move 61 the queens were exchanged. The game reached a RN vs RB position, Clover captured the white passer but Revenge captured a pawn and created a passer on the king side. Clover couldn't prevent a queening and was mated.

game 25, Obsidian - Velvet: The engines opened the center and there were many exchanges, the game reached a RBN vs RBN position with white a pawn up. Obsidian had a pawn majority on the queen side, the white king moved forward to support the pawns. The engines traded pawns and minor pieces, Obsidian created a passer on the queen side. The game ended in a tablebase win.

game 27, rofChade - Revenge: Material was equal but the black pieces had only a little space to move, and rofChade placed a knight on b6. On move 39 rofChade gave a rook for a knight and pawn, creating a passer on the queen side. Revenge gave the material back and the game reached a QRB vs QRB position. After exchanging queens Revenge lost the rook for the passer, the game ended in a tablebase win.

game 36, Obsidian - Clover: Clover gave a knight for two pawns, then a rook for a bishop. The white king was under attack and Obsidian had a trapped knight. Obsidian freed its knight, then gave back a rook for a knight. It surrounded its king with pieces, after exchanging queens the game reached a RBN vs RB position. Both engines pushed a passer forward, eventually both passers were captured. The white king moved forward and Clover lost its remaining pawns. Clover lost more material and Obsidian queened a passer followed by mate.

game 39, Igel - Arasan: The engines castled in opposite directions, Igel captured a pawn. The engines opened both sides of the board, Igel captured a second pawn while Arasan tried to attack on the queen side. Igel reduced to a QN vs QB position and pushed a passer to the 7th rank. Arasan lost its queen for the passer and was mated.

game 40, Seer - Revenge: Revenge gave a pawn early, the engines gradually exchanged pieces until only RNN vs RBB were left. Seer had a pawn majority on the queen side. Seer first pushed a pawn forward on the king side and created a passer, then pushed pawns on the queen side. Revenge gave a bishop and captured the white passers, Seer had enough material advantage to reduce to a tablebase win.

game 46, Arasan - Seer: There were many exchanges after the start and the game reached a RBN vs RBN position with white a pawn up. Arasan had a passer in the center and a pawn majority on the queen side while Seer had a passer on the king side. Arasan captured another pawn and its king moved forward on the queen side. Arasan pushed a passer to the 7th rank, Seer lost a knight for a pawn but couldn't prevent a queening. The game ended in mate.

game 51, Seer - Obsidian: Obsidian moved its king forward in the center instead of castling. There was a long period of mostly shuffling, Seer moved its king back to the center as well and on move 37 Seer opened the h file. Obsidian opened the center and the white king moved to the queen side. Seer moved a rook to the 7th rank and the black king also walked to the queen side. Seer captured a knight and the game reached a QB vs Q position, then Seer reduced to a won king and pawns ending. 

game 53, Caissa - Revenge: Revenge was a pawn up but its king was vulnerable in the center. Caissa gave a knight for two pawns and opened the center, then it gave a rook for a bishop but captured teh black queen for another rook. The game reached a QB vs RRN position, after some shuffling Caissa captured two pawns and created connected passers on the queen side. The white king moved forward, eventually Caissa queened and forced mate.

game 60, rofChade - Igel: There were no exchanges until move 26, then a series of pawn and minor piece exchanges exposed the black king. The game reached a RBB vs RBN position, Igel captured a pawn but rofChade created a passer. rofChade capured the bishop for the passer, the game ended in a tablebase win.

game 64, Caissa - Obsidian: Obsidian castled long and Caissa opened the queen side and exposed the black king. Caissa avoided exchanging queens and the game reached a QRB vs QRB position. Caissa captured a pawn and placed its major pieces on the back rank, Obsidian lost material and was eventually mated.

Standings after RR1: Igel Caissa +3, Seer Berserk +2, Obsidian Arasan rofChade +1, Clover Velvet Revenge Viridithas -2, Minic -5. There are 7 engines with a positive score, it is likely that the two qualifiers will be in this group. Only Berserk has no losses so far, but it has only two wins against lower ranking engines. Caissa beat Obsidian and rofChade but lost to Igel. The picture will be clearer after the reverse games.

game 72, Seer - Igel: Igel was a pawn up from the start, Seer captured two pawns and exchanged queens. Seer focused on the queen side, it traded pawns and went two pawns up with two passers. The game reached a RB vs RB position, after exchanging rooks Seer pushed its passers. The bishops had opposite color but the black king was too far away to help, Seer had a passer on the 7th rank and it managed to reduce to a tablebase win.

game 75, rofChade - Caissa: rofChade created a central passer after a knight exchange. The engines cleared the queen side pawns and rofChade was a pawn up with only rooks and bishops left. The engines exchanged a pair of rooks and after some shuffling the other pair as well. rofChade captured a second pawn, then gave a pawn to created connected passers. Caissa lost a bishop to capture the passers, the game ended in a tablebase win.

game 79, Velvet - Arasan: There were many exchanges after the start and the game reached an opposite color bishop ending with white a pawn up. The white king moved forward, somewhere Arasan played inaccurately and after 40 moves Velvet managed to capture another pawn and create a passer. After another shuffle the engines traded pawns, eventually Velvet had 3 passers and Arasan couldn't stop them all. The game ended in a tablebase win.

game 83, Caissa - Igel: Igel castled long and Caissa created half open files on the queen side using exchanges. Caissa gave a pawn and created a passer in the center, Igel gave a rook for a bishop to captured the passer. The game reached a QRR vs QRN position, Igel was a pawn up but Caissa regained the pawn and exchanged queens. The white king moved forward on the king side, Caissa captured more pawns. Igel lost more material, Caissa queened a passer and mated.

game 86, Seer - Caissa: Caissa captured a pawn on the queen side, Seer opened the king side and exchanged a few minor pieces. After some shuffling Seer regained the pawn and moved its queen forward on the king side, Caissa exchanged queens and eventually the game reached a RN vs RB position. Material was equal but most of the black pawns were on squares of the wrong color and the bishop couldn't protect them. The white king moved forward and Seer created a passer. After exchanging minors Seer went a pawn up, the game ended in a tablebase win.

game 93, Revenge - rofChade: Revenge captured a pawn and created a passer on the queen side. The engines gradually exchanged pieces and the game reached a RRN vs RRN position. Revenge exchanged a pair of rooks and slowly pushed the passer to the 7th rank. rofChade managed to capture the passer, but then Revenge the remaining black pawns and created connected passers on the king side. Revenge queened a passer and mated.

game 101, rofChade - Arasan: rofChade was a pawn up with a passer on the queen side from the start. Arasan gave another pawn and exchanged queens, the engines shuffled for a long time. On move 53 the engines started to exchange pieces and pawns, Arasan captured the passer and the game reached a rook ending. The black king was pushed to the back rank and was in danger, rofChade used this to capture two pawns, then queen a passer and mate.

game 104, Obsidian - rofChade: There were many exchanges after the start and the game reached a QRB vs QRB position. rofChade overlooked something and allowed Obsidian to capture a pawn and create a passer. After exchanging bishops Obsidian connected a second passer and pushed them forward. After queens were exchanged the passers were unstoppable, Obsidian queened and mated.

game 112, Seer - Arasan: The engines castled in opposite directions, Seer pushed pawns on the king side. While Arasan freed a trapped bishop from the corner Seer created a passer in the center on the 7th rank. Seer captured a rook for a bishop,vthe game reached a QRR vs QRB position. Arasan tried to avoid exchanging queens but eventually Seer forced the exchange. Seer pushed another passer, Arasan lost material and the game ended in a tablebase win.

game 117, Obsidian - Seer: The white queen moved forward and captured a pawn on the king side, the black king stayed uncastled in the center. Seer regained the pawn, there were many exchanges and the game reached a RRB vs RRB position. The engines continued to trade pawns and rooks, leading to an opposite color bishop ending. Material was equal but white had a better pawn structure. Obsidian managed to create connected passers on the queen side supported by the king. Seer couldn't prevent a queening and was mated.

game 128, rofChade - Seer: Queens were off early and Seer moved its king without castling. rofChade moved its king as well, the engines exchanged pieces until only RBN vs RBN remained. Not a lot happened until Seer decided to exchange rooks on move 39. rofChade captured a pawn and then created a passer in the center. While Seer blocked the white passer rofChade managed to capture a second pawn, then gave a pawn back and created a second passer. Seer lost its bishop for a passer, rofChade queened and mated.

game 129, Clover - Berserk: The engines castled in opposite ditrections and opened the f file. Berserk pushed a pawn to g6 yet Clover kept its king safe. Clover created a passer in the center, the engines gradually exchanged pieces. Clover captured the g6 pawn, on move 54 the game reached a RNN vs RNN position. Clover created another passer on the king side and the white king moved forward. Progress was slow, Clover kept the black king away and aftere exchanging a pair of knights it pushed its passer slowly. Berserk lost material, Clover queened and the game ended in a tablebase win.

Standings after RR2: Seer Caissa +5, Berserk Obsidian +4, rofChade +3, Igel +1, Viridithas -1, Arasan Revenge -2, Velvet -4, Clover -5, Minic -8. At the half way point there are 5 engines close to the top. Seer and Caissa both have 6 game pair wins and one loss, Seer beat Caissa and rofChade beat Seer. Berserk has no game pair losses but only 4 wins, Obsidian has 5 wins and one loss to Caissa. rofChade has 1 loss to Obsidian and 4 wins. Igel also has a positive score but it drifted away from the leaders. Arasan is far from the leaders after 2 game pair losses and no win in the reverse games. For some reason Clover crashed 4 times on time in RR2, in three games it was close to losing anyway - perhaps its was of resigning. It crashed once in a drawn position against Viridithas. 

game 140, Berserk - Igel: The engines exchanged minor pieces and Berserk created a passer in the center through such an exchange. After some shuffling Igel created a passer on the queen side and the game reached a QRR vs QRR position. Berserk captured two pawns and protected its passer, the engines exchanged a pair of rooks. After Berserk captured the black passer it pushed its own passer forward, Igel exchanged queens but it was mated on the back rank.

game 141, Caissa - rofChade: There were a few pawns exchanges after the start, the first minor piece exchange was on move 24. Caissa captured a pawn, it moved both its knights to the queen side where they were very effective together with two pawns. rofChade gave another pawn and the game reached a QNN vs QBN position. The black queen tried to attack but was too weak and Caissa found safety for its king. Caissa captured another pawn and created passers, then forced a queen exchange. rofChade lost its pieces for passers, Caissa queened and mated.

game 162, Berserk - Caissa: Caissa castled short despite the fact that its g pawn was gone. The black queen captured a pawn on the queen side, Berserk moved its major pieces forward and Caissa manually uncastled its king. The engines exchanged pieces until only RRN vs RRN remained, Berserk captured pawns until it was two pawns up. The engines reduced to a rook ending and the game ended in a tablebase win.

game 165, Minic - Seer: The center was blocked, Seer equalized quickly. Minic opened the queen side and tried to attack, Seer gave a bishop for a pawn and opened the king side. Minic captured a rook for a bishop, the game reached a QRR vs QRN position with black two pawns up. Seer ethreatned the white king on the g file and created a passer on the queen side. Minic exchanged queens and blocked the passer on the 2nd rank. Minic captured the passer and Seer created another, the black king moved forward and the white king couldn't help. Minic lost material and the game ended in a tablebase win. 

game 167, Arasan - rofChade: The engines castled in opposite directions and the center was blocked. Arasan gave a bishop for a pawn and opened the king side, rofChade opened the queen side. Arasan gave a rook for a bishop and pawn attacked the black king. rofChade gave back the material and the game reached a RN vs RB position. The white knight was much more effective, Arasan quickly captured two pawns, it had two doubled pawns but one pair were passers. The white king moved forward, Arasan captured more pawns and created another passer. Arasan queened and mated.

game 170, rofChade - Obsidian: rofChade pushed pawns on the king side and captured a pawn, leaving its king a little exposed. Obsidian was not able to take advantage of this weakness though both its knights were active on the king side. After some shuffling Obsidian gave a rook for a knight, this created a passer and opened the queen side. rofChade also created a passer and pushed it to the 7th rank. The game reached a QRR vs QRN position, Obsidian gave a rook in a desperate attack on the white king. rofChade queened the passer, exchanged a pair of queens and mated.

game 180, Clover - rofChade: The engines castled in opposite directions, after a few minor piece exchanges the king side opened and Clover captured a pawn. The game reached a RB vs RB position, Clover had a pawn majority on the king side. rofChade tried to protect its pawns but eventually Clover captured a pawn and created connected passers. Clover slowly pushed the passers with the king's support, rofChade lost the rook for a passer and the game ended in a tablebase win.

Standings after RR3: Berserk +8, Obsidian Seer Caissa +7, Igel rofChade +2, Viridithas 0, Arasan -2, Revenge -5, Velvet -6, Clover -7, Minic -13. The leader pack is down to 4 engines, rofChade was dropped after a weak RR that included losses to Arasan and Clover. Berserk has a small lead at the top, its results in RR3 were better than in RR1 with wins against Caissa and Igel. Obsidian, Caissa and Seer had similar results in RR3 as in RR1. Caissa beat rofChade and Obsidian lost to rofChade, the remaining wins were in games against lower ranking engines. Seer is still in joint second place due to an unexpected win over Minic, in black against the bias. The reverse games will determine which 2 engines will advance to the premier division. 

game 203, Berserk - rofChade: Berserk opened the king side and exposed the black king. After a series of exchanges the game reached a QR vs QBN position with white two pawns up. Berserk had connected passers on the king side, after some checks and some shuffling the engines exchanged queens. Berserk captured the remaining black pawns and slowly pushed its passers. The game ended in a tablebase win.

game 215, Caissa - Igel: The engines castled in opposite directions, Caissa attacked on the king side and Igel exchanged queens. The game reached a RBN vs RNN position, material was equal but Caissa had a passer on the king side. The white king crossed the board and moved forward to support the passer. Caissa moved a rook to the 7th rank, while Igel was busy defending on the king side Caissa captured two pawns on the queen side. Igel lost material and was mated.

game 216, Berserk - Seer: There were almost no exchanges after the start, Berserk pushed pawns on the queen side. On move 27 Berserk gave a rook for a bishop, then the engines shuffled for a long time. After move 61 a few exchanges opened a file on the queen side, the engines exchanged a pair of rooks and then opened the king side. The black king was in danger, and Berserk pushed a passer to the 7th rank on the queen side as well. Seer captured the passer but in a series of exchanges lost material and the game reached a BBN vs N position. The game ended in mate.

game 225, Revenge - rofChade: Queens were off early and the black king moved and blocked the queen side rook. The white king stayed in the center but its rooks were free. The engines exchanged a pair of rooks, Revenge gave a pawn to create a passer on the king side while giving rofChade connected passers there. However, the game reached a RBN vs RBN position and Revenge captured two pawns on the queen side, creating another passer there. rofChade lost its knight for a passer, it managed to push a passer to the 2nd rank but there it was stopped. Revenge trapped the black king and mated.

Standings with 5 rounds to go: Berserk +12, Obsidian +9, Caissa +8, Seer +7, rofChade Igel +2, Viridithas -1, Arasan Revenge -5, Clover -7, Velvet -8, Minic -14. Berserk broke away from the other engines, it beat Seer and rofChade and is comfortably in the lead. Obsidian's results were as expected with two wins as white against lower ranking engines. Both Caissa and Seer drew a few games they needed to win, they need to do better in order to have a chance of advancing.

game 239, Minic - Berserk: The engines castled in opposite directions, there were only a few exchanges after the start. Berserk equalized, then opened the queen side. Minic countered with a knight sacrifice to open the king side, it placed all its major pieces on the h file. Berserk kept its king safe, after some shuffling the engines exchanged a pair of rooks. Berserk shifted to attack the white king, it captured pawns and reduced to a QBB vs QB position. Minic was still a pawn up but Berserk managed to exchange pieces and reduce to a tablebase win.

game 240, Viridithas - Caissa: Both engines castled long, Caissa was a pawn up but Viridithas developed its pieces faster. Caissa gave the pawn back, after a series of exchanges the game reached a QRB vs QRB position. Viridithas captured two pawns and created a passer on the king side. Caissa gave a rook for a bishop and captured back two pawns. Caissa avoided exchanging queens but lost its bishop for the passer. Caissa delayed with checks but eventually the game ended in a tablebase win.

Standings with 2 rounds to go: Berserk +13, Obsidian +9, Caissa Seer +8, rofChade+2, Igel Viridithas +1, Revenge -5, Arasan Clover -6, Velvet -9, Minic -16. Obsidian kept its small lead in second place, Seer and Caissa are still close. Caissa nearly caught up to Obsidian but lost unexpectedly to Viridithas, Seer improved its score a little and is in joint third place. Obsidian still has to face Berserk and Caissa, while Caissa and Seer both have a game as white against lower ranking engines. We may see a tiebreak for second place, currently Seer has a game pair win against Caissa and Caissa has a game pair win against Obsidian. 

game 256, Berserk - Obsidian: Both engines castled long and both queens moved forward. Both engines pushed pawns forward, Obsidian opened the g file and Berserk opened the c file. The white king was more exposed but Berserk was the one attacking. Berserk captured a rook for a bishop and two pawns, the game reached a QR vs QB position. Berserk used checks to capture pawns while Obsidian gave checks to delay when possible. With white a pawn up the queens were exchanged, Berserk queened a passer and mated.

Caissa and Seer drew as white against Arasan and Clover. Together with Obsidian's loss the three engines are tied at +8 with one round to go. Seer has the tiebreak advantage under these conditions.

In the last round Seer drew as black against rofChade. Obsidian had one last chance against Caissa but this game also ended in a draw. No change in the standings at the top, Seer finishes in second place on a triple tiebreak with Obsidian and Caissa.