“Othello Is Solved”, Hiroki Takizawa2023-10-30 (model-based RL)⁠:

The game of Othello is one of the world’s most complex and popular games that has yet to be computationally solved. Othello has roughly 10 octodecillion (10⁵⁸) possible game records and 10 octillion (10²⁸) possible game positions. The challenge of solving Othello, determining the outcome of a game with no mistake made by either player, has long been a grand challenge in computer science.

This paper announces a milestone: Othello is now solved. It is computationally proved that perfect play by both players lead to a draw.

Strong Othello software has long been built using heuristically designed search techniques. Solving a game provides a solution that enables the software to play the game perfectly.