Ice Slave

Ice Sleep is a Caster Magic.

Description
Using a collar that is conjured around his target's neck, the user can control the affected's thoughts and actions. When used on Mavis, she described this Magic as if her thoughts were being snatched away, being unable to think rationally and her body listening to the enemy's orders, moving on its own. It is also stated that it steals the identity of oneself and is approximate to completely freezing one's heart solid.