Incredibly well done, could've fooled me into believing this was done with a team! I really liked the concept, it was fun to play and the rock, paper scissors foundation made it pretty easy to pick up on the core concepts. I would second some of the feedback that a little more variation in the outcome UI or sfx could have made it a little easier to catch on to the unique mechanics of this game (counters, combos, etc.) but after reading the in game guide (a fantastic addition for a jam game by the way!) I'd say it's pretty manageable to put 2 and 2 together for most of that stuff.
Loved the music as well. Had such a mood and aura to it, it practically put me in a trance just sitting in the menu. I also really liked the take on the theme as well. For a fighting game it would've been really easy to have gone the obvious route there but the idea of the mental burden coming into play and forcing the player to chose new characters was really neat. Really, really great work overall- and it's awesome to read that you're working on a post jam version too!