20 tiles fill the grid. Exactly one pair of identical icons is hidden among them. All other tiles are unique.
Tap one tile to select it — it glows yellow. Find its exact match and tap it. Correct: both dissolve, new grid spawns instantly.
Near-identical icons appear later. They look similar but are not the pair. The pair is always identical — not just similar.
Score carries. One wrong tap resets your streak and briefly stuns the grid. One chance per day.