Cork and Drain puzzle. To cross the gap the character will need to use the mast as a platform and push the cork. The cork will block the drain and create a platform for the character to get across to the other side.

Octopus puzzle. The character has to move in time to avoid the tentacles.

Concept for the cork and the drain.

Simple puzzle idea, the character pushes a plank to make a ramp. Sea Urchin monster is safe to touch when sleeping as its spikes are retracted. When awake the spikes come out and become a hazard.

Possible background ideas for fish. Can be duplicated to form a school of fish.

Geyser pushes character upwards.

Clam hazard. Character cannot pass when the clam is closed. When open the character must be quick to avoid it closing on him.