I never understood how he was able to kill him that way. It didn’t seem that his explosions really hurt him at all up to that point. He can withstand the sun, and being beaten nearly to death by his dad, but a bigger Rex explosion can kill him? Weird.

Also, if they hadn’t planned on killing Rex, I always thought a really cool twist would have been if he grabbed Mark’s arm and just said, “You.”

Better he went out like a g here, cuz he wouldn’t have gone along with Robot’s bullshit and he would have died much worse at his hands.