Swell

you can only grow while nothing is touching you.

hold an ink blot to grow it; touch it while growing and the sheet collapses to bare ink. reach a hundred

Hold a blot and it grows, counting toward a total of a hundred. Blots can drift into each other freely, but one touched while growing collapses the whole sheet back to bare ink: the game is reading the drift and releasing before contact, not growing fast.

Concepts: constraints, timing.

An interactive you play with one thumb, on Wundr.