Overview — Luna (Xiaowen) Cao (kazuko-chan)

Luna (Xiaowen) Cao, known online as kazuko-chan, is a dynamic chess player who made a name for herself in Rapid play. A fierce tactician with an appetite for tricky opening lines, Luna combines deep endgame knowledge with an uncanny ability to recover from difficult positions — often to the astonishment of her opponents.

Preferred time control: Rapid. Peak highlights: 2697 (2026-02-04) and 2814 (2026-02-25). See recent trajectory:

Playing style & key stats

Luna’s games are characterized by long, strategic battles that tend to finish in endgames. If chess were a movie, most of her matches would be slow-burn epics with a surprise twist ending.

Endgame frequency: 81.4% — Luna loves the theater of the 2nd half of the game.
Average moves per win: ~79 — patience is a superpower.
Comeback rate: ~80.8% — losing a piece? Don’t panic, she’s probably already calculating the comeback.
Best time of day to play: 10:00 (local) — peak performance hour.
Preferred time control: Rapid (plays consistently and often best at this control).

Strengths include exceptional tactical awareness (notably high WinRateAfterLosingPiece) and a strong tendency to grind opponents down in long, practical endgames.

Favorite openings — what Luna plays and why

Luna favors systems that offer solidity with tactical chances. She’s famous for using the London System in subtle, aggressive lines and handles many Sicilian and English structures with precision.

London System: Poisoned Pawn Variation — a Rapid staple (179 games, win rate ~74.9%). See London System.
Sicilian Defense: Taimanov Variation, American Attack — a common Black reply with strong scores in both Rapid and Blitz.
Sicilian: Alapin & Sherzer variations — used to steer games into familiar, winning terrain.
Amazon Attack & QGD setups — flexible choices that lead to middlegame richness.

Want to study one of her lines? Try this short sample (London-ish feel):

Career highlights & notable games

Luna’s career reads like a climb through tactical forests and strategic mountains — with plenty of rapid-fire skirmishes along the way. She has an impressive record versus several frequent opponents and several multi-game streaks that have become small legends in her online circles.

Big streaks: longest winning streak — 40 games in a row (yes, forty).
Current form: currently on a 1-game winning streak; longest losing streak — 10.
Notable opponent performances: perfect or near-perfect records against players such as chessman_onyoutube and ghostyphas (multiple wins, often without losses).
Study this tactical showpiece: Blitz masterpiece — a crisp example of Luna’s endgame conversion and tactical vigilance.

Openings performance snapshot

Rapid: dominant with the London Poisoned Pawn and several Sicilian lines; Blitz and Bullet show aggressive, high-scoring peaks as well. Below are a few of her top-performing lines.

London System: Poisoned Pawn Variation — Rapid: 179 games, ~74.9% win rate.
Sicilian, Taimanov / American Attack — frequent choice with strong results in Blitz and Rapid.
Alapin & Sherzer — reliable sidelines that often lead opponents into unfamiliar territory.
Australian Defense (Bullet) — tiny sample size, huge success: ~91.7% win rate in that line.

Learn more about specific openings: London System · Sicilian Defense · Alapin Variation.

Records, training habits & psychology

Luna’s profile is full of long decisive games and a noticeable preference for preparation depth — she increases her median prep depth over recent years and prefers slower, more technical workshops.

High durability: wins much more often when playing below or equal rating; excels at grinding wins vs weaker or equal foes.
Tactical resilience: WinRateAfterLosingPiece ≈ 54.8% — she often turns material deficit into practical chances.
Training hints: long average game lengths and strong endgame play suggest hours spent on technical endgame studies and practical conversion drills.

Fun facts & personality

Nickname: kazuko-chan — used widely across her online accounts.
GIF-ready reactions: known to celebrate with exactly the right meme at the 40th consecutive win.
Best time to challenge her: aim for 10:00 — she’s statistically sharpest then. Don’t try 9:00 unless you brought fireworks (her win rate at 9:00 is a mystery).
She’s a finisher: an impressive average moves-per-win and a love of long endgames mean she’ll make you sweat.

Want to follow her games?

Track Luna’s Rapid journey and sample games above. For a quick look at peak numbers: 2697 (2026-02-04) · 2814 (2026-02-25). Explore a memorable game replay: View Game.