The L Game

• Each turn you must move your L-piece to a new position — slide, rotate or flip it anywhere it fits on empty squares. It has to end up covering at least one different square.
• Then you may move one of the two bone counters to any empty square — or skip.
• If you cannot move your L-piece at the start of your turn, you lose.

Owned counters is a house variant: each counter wears a ring in its owner's colour, and you may only move your own. de Bono's original rules use shared counters — either player may move either one.

Drag your L around the board; press R to rotate and F to flip while holding it (or use the buttons). Tap once to pick a piece up, tap again to place it. Esc puts it back.

Invented by Edward de Bono and published in The Five-Day Course in Thinking (1967) — designed to be the smallest possible "real" strategy game.