[Don suddenly heaves at that, covering his mouth.] Oh shell, never ever call Karai that again. [Ew ew the thought of her being their Gram-Gram in another world while his brother was mooning over her makes him nauseous.]

A demon possessing armor is a way to put it. He's an Utrom. They're these small, highly intelligent, mostly immortal aliens. He piloted a human suit for I don't even know how long. Obviously damaging the suit didn't hurt him, but even if you thought you got him, he could still regenerate. Eventually we just had to hand him over to other Utroms to take back to their home planet. [The corner of his mouth pulls, a shadow coming over his eyes for a moment. He has a flash of memory--a giant mech suit. Standing over the shredded viscera of Ch'rell... and all the corpses of his brothers.] Or you'd have to vaporize him with an energy drill so there's nothing left to regenerate.

[Donatello shakes his whole body out to dislodge the memory, blinking it away.] But none of that really matters right now, right? They're not here. You and I are. And we need to figure out how we're going to manage until we figure out going home.