A mysterious figure who appears in Super Smash Bros. Brawl's Adventure Mode, The Subspace Emissary. They're in charge of deploying Subspace Bombs to assigned locations.
It is actually a R.O.B. who was forced into an antagonistic role. After the rest of its race is forced to sacrifice themselves to detonate the rest of the Subspace Bombs, it promptly joins the heroes to save the day.