Which game dates back to at least the Roman Empire: Nine Men's Morris, or Icehouse pieces?
Icehouse pieces Icehouse pieces, or Icehouse Pyramids, Treehouse pieces, Treehouse Pyramids and officially Looney Pyramids, are nestable and stackable pyramid-shaped gaming pieces and a game system. The game system was invented by Andrew Looney and John Cooper in 1987, originally for use in the game of Icehouse.
Wythoff's game Wythoff's game is a two-player mathematical game of strategy, played with two piles of counters. Players take turns removing counters from one or both piles; when removing stones from both piles, the numbers of counters removed from each pile must be equal. The game ends when one person removes the last counter or counters, thus winning.