The gameplay is all about jumping around on stones in the river, trying not to get caught by the Bocondas. You can jump by placing a cursor above a stone, but if you don't do it right, you'll end up in the water instead. The current can sweep you away, so you have to be careful where you go.
The bananas are your best friend in this game. You need them to get rid of the Bocondas, and they can be placed on top of stones to trap the enemies. However, the Bocondas are smart and will try to jump at you if they think it's safe. You'll have to trick them into jumping onto a banana or use your wits to throw stones from the shore and make them fall off their own stones.