Thundrus & Snooze

Killer - A unit with Killer can make one special attack directly against an enemy unit. This can be done the turn it's played, and can target any unit, regardless of Flying, Aegis, or other special abilities.

Summon - Does something when played

Stun - Exhaust a unit. It can't attack or block next turn.

Regen - The first time this would be dealt damage, prevent all of it.