oh! I think you only beat the first boss! :) The chest gave you the ability to breathe underwater, which allows you to go to a different part of the level. You need to backtrack 2 rooms and go down to continue
Ahh I see. I didn't know what it did but that makes sense
That's definitely on us to make it a lot clearer, so that's great feedback :)
If you get stuck, here's the full gameplay walkthrough
