Tumbling doll down だるま落とし

i-SOBOT plays Tumbling doll down. Tumbling doll down (Daruma otoshi) is a traditional Japanese toy which stacks five or so thick discs made of wood. The objective of the game is removing all the wood discs by hitting the bottommost disc with a wood hammer. If you hit well enough, all the discs will not fall down because of the inertia.