Great prototype, big fan of the roguelike deckbuilding elements and the idea of sharing energy between movements/attack/defense.
It might be nice to give some benefit to passing a turn or ending with excess energy, because a lot of the time I ended up with no reason to actually do anything on a turn (ie moving would put me out of range or open me up to attack and I had no defense cards) and repeatedly passing turns waiting for attack cards is a little boring. I could be wrong though, maybe once encounters become more varied/fleshed out with more enemies and obstacles this wouldn't be a problem.