Unfortunately I didn't have much time to fine-tune the boss or test its jumping. I'll see what I can do to fix that in the future. I think the issue may be that he needs to chase the player too if he can't get a clear shot. But he was implemented on the last day. He was horribly lethal at first, so I was focusing on bringing his lethality down. I suspect if you'd jumped right under him where he was stuck, he would've jumped to a new lower position. But he should be fixed so you don't need to do that. The AI looks for a dozen jump points on the map, sees which ones are visible to it, and then jumps towards one at random. He may have just randomly kept selecting the same one - or it may have been the only one he could see and that's something I need to check. Ultimately, I think a more open design with ledges only on the wall might've worked better.
I'm curious how you felt the music didn't fit. That's the first time I've gotten that comment, but I wondered about different music in the mine. I went through three different songs before settling on that one.
The characters are a little on the small side. That's a good point about the attack animations. I'm doing another game jam now with the same characters, and I'm using Godot's 2D skeleton and parts of the characters instead of frames of animation. So it's easier to play with the size of different parts.
Yeah the double jump comes after the boss., and there were shrink slide and colossal kick abilities that didn't get implemented that would've gotten you under ledges, through rock walls, and opened the large and small doors.
Thanks! And thanks for the feedback.