The chasm is full of gaps and solid rock.
Tap a gap to drop a plank on it — tap the plank again to take it back.
Your budget is tight: only the planks you spend on spares pay extra.
Press CROSS and the walker takes the best path across.
No solid route bank-to-bank and the walker falls — the run ends.
Clear all 10 chasms. Each clear banks 10 + 3 per spare plank.