Curate, connect, and discover
I really like the idea of an undead rodimus au.
He got the matrix after getting his spark blown up and deing. so I like to think instead of giving him a new spark, the matrix just replaced his spark with itself. And so after it got separated from rodimus he was left with no spark, but he still lived.
He now lives without a spark and cannot die. If his head gets cut of, he can just put it back no problem, it also works with all his other parts.
He knows he can't die in a normal way, but he forgot to tell the others. So one time during a fight or during the mutiny, something happens and everyone finds out. I imagine it goes something like that:
Rodimus: *looses his head*
Everyone else in the battlefield: *stop fighting and looking*
Rodimus: *gets up of the floor and puts is head back in place* well that was annoying. And my head is gonna be wobbly for hours now.
Everyone: *horrified*
Rodimus: what? Did I do something wrong?