Atlantis
After each move you seal one square on the edge of the board.
The board sinks from the rim inward. Rooks lose their long files first, and a king tucked in the corner can end up with nowhere to stand. Deciding which edge to drown is a real part of the plan.
What changes
The board starts the same way standard chess does.
Standard chess: Classical chess. Checkmate the king.
1 augments run on this rule
- Atlantis After each move you seal one square on the edge of the board.