I've seen this mechanic a couple of times during this jam, but yours is slightly different in that the characters can roam around freely. I like the freedom and it opens the play up for more obstalces/puzzels.
I like the mechanic to have mana and firebolts, it sounds trivial but something about it just feels right.
The art-style and music fit really well together, I think you did a great job on that.
Congrats on submitting!