Svyatoslav Korneev Leskova
Known online as KoshkaMatrioshka, Svyatoslav Korneev Leskova is a FIDE Candidate Master, a streamer, and one of the most persistent bullet players in the scene. The username may translate roughly to "cat nesting doll", but there is nothing cuddly about the way he converts winning endgames. His preferred time control is Bullet, and the rating history shows exactly why: he has made a career out of turning chaos into checkmates.
The Cat Who Chases Bullets
Leskova first appeared on the rating boards in 2018 with Blitz swings between 1806 and 2320. From there, the climb was steady and occasionally explosive. By 2021 he had crossed 2500, and in 2026 he reached 2853 (2026-07-28) in Blitz and 2914 (2026-09-09) in Bullet, with 2480 (2026-05-05) in Rapid along the way.
His longest winning streak of 35 games suggests that when the cat gets going, the mice have very little time to react.
A Repertoire Built for Speed and Grinding
As White, Leskova is a loyal servant of the English Opening, almost always opening with 1.c4 and steering into lines like the Agincourt Defense. As Black, he leans on the French Defense, especially the Exchange Variation and the Winawer Advance, where he punishes rushed attackers with patience.
The numbers back up the approach. His White win rate sits at 59.42 percent and his Black win rate at 56.11 percent, which means he is dangerous from both sides of the board.
Comebacks Are His Comfort Zone
This is where Leskova becomes genuinely scary. His comeback rate is 87.26 percent, and he wins 55.39 percent of games even after losing a piece. One-sided losses happen only 1.26 percent of the time. He almost never resigns early, with an early resignation rate under one percent, and he loves the long game. His endgame frequency is 86.26 percent, with wins averaging over 88 moves.
- Longest winning streak: 35 games
- Comeback rate: 87.26 percent
- Win rate after losing a piece: 55.39 percent
- Endgame frequency: 86.26 percent
Opponents who expect a quick resignation are in for a long evening.
Rivalries and Recurring Opponents
No biography is complete without a friendly rival. Against arualplays, his most frequent opponent with 165 games, Leskova won 159 times. That is a 96.36 percent score, which stops being a rivalry and starts being a ritual. The tougher test comes against GMRusty, where the score is much closer at 28 wins, 22 losses, and 2 draws.
Streamer Life and Weird Hours
As a streamer, KoshkaMatrioshka brings the same mix of calm and chaos to every broadcast. The data suggests he plays best around 4 a.m., where his win rate in that hour is a perfect 100 percent, though the sample size is gloriously small. Fridays are his strongest day, with a 63.25 percent win rate, and his tilt factor of 17 is impressively low for someone who spends so much time in bullet time.