Teleport- Most OP spell ever. Consider significantly reducing or removing altogether the damage. Or reduce the range. Or make it blockable by physical armor. It is just too damn good. Moving a character across the map is so powerful in this game, it also dealing a spells worth of damage and not being blockable with armor is too strong. In a game like this, its not competitive, sure you can have OP spells, but honestly it is worth a point in Air magic and the teleport spellbook to have this spell on every character.
Teleport should require air magic on level 2 or 3 and the problem would be solved. That way probably only one or two characters in your party can cast it. And with its three turns cooldown it's imo correctly balanced.