From the problem cellar
Reversi problems
30 positions in three difficulties. A tick marks the ones you have solved in this browser.
Trap a line of discs and turn them to your colour; the corners decide.
Easy · #501–510
Two turns to a corner: the first move must leave the opponent only replies that open one.
Medium · #511–520
Eight empty squares, and one move wins. Count parity: who gets the last move in each region?
Hard · #521–530
Eleven empty squares and a single winning move. Expect a pass or a quiet move somewhere in the line.