"Fenrir, I will cover your claws with dark magic. I believe you're the only one who could stop this dog from going berserk," I confessed, while preparing the spell. "I need a minute to prepare this spell. Until then, Merleen, protect all of us with your light!"
As I laid out my instructions, Merleen cast some protective light spell on our bodies, especially on me. If I needed to use my black magic on Fenrir's claws, I needed to wait around a minute to cast it. We gamers called that "channelling" our spells, focusing both my mental and physical state to activate my abilities.
If I got distracted from my channelling spell, I would lose the ability, rendering my magic useless. But if I successfully channelled the skill, the magic circle would activate itself.
