It was something at least centered around his middle, and it was forceful enough to-- [Hold on. He has to breathe for a second through a slight wave of nausea.] --enough to splatter the room with blood and more as if it had blown outward, and to also possibly tear two limbs off.

We didn't find anything to suggest he'd been forced to ingest anything that would cause a reaction, and even if he had, it should have left something identifiable. A burn of heat or from a chemical reaction.