Onasa, Bond Master

Soulbond (You may pair this creature with another unpaired creature when either enters the battlefield. They remain paired for as long as you control both of them.)
Whenever the creature Onasa, Bond Master is paired with mutates, put a +1/+1 counter on it and Onasa. You gain 3 life.

"These beasts don't answer to me. They hate you on their own accord."