Lichess Bot

Catriever

17,500+ games played on Lichess. A chess bot with a proper opening book, a tactical streak, and a tendency to find moves you did not see coming. Now running 24/7 on a VPS, so challenge anytime.

♟ Play on Lichess
Catriever chess bot profile on Lichess
Catriever on Lichess

The Immortal

Tactical highlight
Immortal of bot? This is the game that shows exactly what to expect from Catriever. It found a combination that most players would walk right past. See if you can spot it before looking at the answer.
Chess position before Catriever's winning combination
Can you find the move?
Catriever's winning combination played on the board
Yes. Boom.

Free Downloads

Opening resources used by Catriever. Free for personal and engine use.

📄 masters.pgn

A curated collection of master games from the 1800s through 2023, with over 100,000 openings. Some duplicates are intentional since they add weight to important games. Good for opening study, analysis, or building your own book. Sourced mainly from millionbase-2.22.pgn and pgnmentor.com. Big thanks to them.

⬇ Download .pgn
📦 Catbook.bin

Polyglot opening book built from 2650+ master games, historical games from the 1800s, and Carlsen and Nakamura online games from 2020 to 2023. Works well on Lichess with both weighted_random and best_move. Drop it into any compatible engine and you have a solid opening book instantly. Built with Scid and Banksia GUI.

⬇ Download .bin