Official Thread - Metal Gear Solid V: The Phantom Pain

[Bio]

My guess is that it's Psycho Mantis' (or a similar character's) hallucinogens. You certainly see someone looking awfully like him at the end of the trailer. And he's floating behind one of the enemy soldiers, too, as if he's been assisting them the entire time.

The doctor doesn't even mention his arm. Makes me wonder if the arm is a hallucination, too. After all, he can't "feel his body" anyways. Probably part of the side effects.