Collars

Collars (aka forbidden action) prevents you from doing something, if that happens you will be injected with a poison, they could make a normal forbidden action, a forbidden action that requires you to murder, or a forbidden action that prevents you from doing your skill.

Facts about the collar
trying to get the collar off, don't the collars have a bomb that makes it so when you try to tamper with the device you explode. The poison could be different depending on what your role is or just a normal poison,