Outer Rim Adventure
Overcharging is when you make an Arcane Discipline 10 Skill Difficulty more powerful than the amount of Arcana Skill you have.
Example: Jadis, at level 5, has a Arcana Skill of 13. She can cast a spell of 5-10 Skill Difficulty with ease (no roll). She can cast a spell of 15-20 Skill Difficulty with a roll of a d20 plus her Arcana Skill without losing the spell if she succeeds. A spell she tries of 25 and over will “overcharge” and wether she succeeds in the roll or not, the spell is lost.