Bug: if you've clicked on the other side of a flag, you'll walk around it, but if you click across it again while passing it, you'll trigger the mine despite the flag being there.
Not a fan of the fact that there seems to be no way to retrace your steps (and therefore complete the game) if you do anything in the wrong order (i.e., summon drowned early, or forget the potion bottle before you make the potion).