Nice! The combat system is great and with it you could make a dungeon crawler or a tactic rpg. Some ideas I had while playing: it would be nice to have  a "restart" button after finishing a fight. There could be random walls so every combat is unique. I found a little bug: my character can walk over the top and left wall.

It's a fun little game! A have a couple of ideas and things to change:

Add sound effects, Bosca ceoil is great for music and  SFDesigner is ground for making some basic sounds. 

Add a way to view what each ability does for each character

The wizard is way super overpowered you can easily fireball spam any enemy most battle the wizard wins unless everyone else was to team up on him, I recommend making him weaker maybe he can only use a fireball once per turn.