Enigma of Combination

{x}{x}{t}: Exile X Artifact Creatures you control.
Create a Combiner Artifact Creature token whose
Power is equal to the total Powers of the exiled Artifact Creatures added together, and whose Toughness is equal to their total Toughnesses.
The Combiner has Trample, in addition to all abilities of the Artifact Creatures exiled to create
it. If the Combiner dies, return the Artifact
Creatures that were exiled to create it to the battlefield tapped.
"Constructicons, unite!"