How to Beat Crystal Sage?
Crystal Sage is one of the easiest bosses of the game. You need kill him. If you have in your inventory armor which increases magic resistance, then this fight will be easy.
Run instantly point-blank of the enemy and attack him all that you can. Soon, the enemy must dissolve in the air. He appears in one of the few points on a very compact battlefield. Stand in the center of the arena that might like to run up to him as soon as possible. If you see the crystals, it is best to destroy them before it's too late.
At the second stage the enemy will dissolve more often in the air. There will be a spear, you must destroy it.