Swipe ← →: the block rolls sideways and its width changes.
Swipe ↑ ↓: it rolls up or down and its height changes.
Rolling keeps a rhythm, so a spot can only be reached in one shape…
…unless you bump a wall. Rolling into a wall changes the block's shape in place, which shifts its rhythm. Rolling onto a dark hole loses. Land exactly in the glowing goal, in its shape.
Cracked floor holds small shapes, but breaks under the big square.
Shape tiles only hold the shape drawn on them.
Switch flips every bridge each time you land on it.