Metellos was the overpopulated crap-hole planet that tried to be Coruscant, but failed miserably. Like Coruscant, Metellos was an ecumenopolis, a world-spanning city... but Metellos was 100% ghettos and slums. Unemployment on Metellos was roughly 79%. The local government long ago gave up on any kind of welfare system; the only thing Metellos provided to its citizens was crystal meth.
Every few years, a superhero, usually dressed like a bat, tried to fight crime on Metellos and was typically murdered within a week. Honestly, the Death Star really should've blown the planet up long ago. The only thing worth saving would've been the Metellos Pistons... and they could've been safely relocated to Planet Basketball.