Stolen Heart

Create an artifact token named "Heart", then exile target creature. It remains exiled for as long as you control your heart. At the beginning of each end step, if you control your heart, you gain 10 life.
When your heart leaves the battlefield, you lose the game.

"That appears to be... YOUR HEART! That means the Blot can enter your world when he gains enough strength!"
—Gremlin Gus