Shuffle

the empty square is your only tool.

drag the hole around the tray until the ring closes

There is only one gap, the only thing in the tray that can move. Drag the hole, and each square it enters ends up where the hole just was: the tiles are never what you move, they are the wake the hole leaves behind it.

Concepts: puzzles, logic.

An interactive you play with one thumb, on Wundr.