How in the actual hell do you:
1. become stronger
2. beat the living armour when you do fuckall damage
3. do anything other than bitch slap the enemy
Progressing the story unlocks better versions of your spells, just remember to go talk to your magical mentor whenever you have the option to get those improvements
The armor has a shutdown code. Won't beat it outright, but searching for it in the abandoned fort or w/e
will give you a significant edge when fighting the one controlled by the bandit dudes
Also, remember that you have other spells beyond the basic energy blast. Using them really does help most of the time.