Great submission, firmly on the theme. When I got to penguins and they seemed to wave at me, I tried talking to them... but they just killed me on spot :D .
Two suggestions
- pause slightly on death so player can be sure why they died ‒ falling a long drop can lead to such a quick death I was sometimes not able to notice how close to some ledge down there I landed (or whether the bottom is just full of spikes)
- on death keep all collected coins ‒ in current levels it is not much a difference but as it is a coin being collected it makes more sense to me to retain already collected ones