Magic, first of all, is available in runes and scrolls. Once your character has learned a new rune, if his magic skill is high enough, and he has enough available mana, then he can cast the spell. Spell casting is performed by drawing runes on the screen using the mouse. It is similar to the way the game Black and Whitehandled magic, but it is fortunately much more forgiving in Arx Fatalis. What is difficult though, is remembering the runes, as there is no way to pause combat in order to 'look them up'.

There is some help in this regard, though, as you can open the spell book, select a spell, and the runes will appear in the upper right hand corner of the screen. As you then draw each rune, the corresponding helper rune will highlight, and once the spell has been successfully cast, they will disappear altogether.​