Heartbeat . . . Or Not?

The last thing Cassian could remember was pain-the pain of being shot through the heart-the pain of drowning miserably alone in a dark ocean. His death, or so he thought.
So why then does he now find himself in a new body with the same pain he felt in death? And why doesn't his heart beat? And, is that blood?

"When we said kin iron man this isn't what we meant"