Just typing out loud with an idea that’s been floating around in the back of my mind for a few days.
Thief Advanced Move (6-10)
By the Book
Your experience with the supernatural has slowly translated into the ability to read the magical script of wizards. You can cast spells from scrolls as a wizard of 5 levels lower. When you read from a scroll, roll+CHA. On a 10+, the spell effect takes place and the scroll remains. On a 7-9, the spell is cast but the scroll disintegrates and you choose one:
*Not being an expert, it’s easy for something to slip up. The spell isn’t quite right.
*While you knew what you wanted to do, and who you wanted to do it to, one or more of your companions are caught up in the effect.
*The scroll demands more power, and sucks away 1d6 of your own life force.