Morgg is the main antagonist of the Ben 10 Ultimate Alien episode ...Nor Iron Bars a Cage. He is the prison warden of the Null Void and an intergalactic drug dealer who forces the Null Void prisoners to dig for drugs. He was voiced by Xander Berkeley.
Not much known about Morgg's early life but what is known that he starts out as a guard at a prison in the Null Void. When he sees Kwarrel being fatherly towards Kevin Levin and he discovers blue crystals that can create hallucinations, like drugs which he uses to make a prison riot. Kwarrel along with Kevin escapes through hole he was digging but they find Morgg. Morgg aims a gun at Kevin but Kwarrel stops Morgg, letting the boy escape from the Null Void. Morgg shoots Kwarrel to death which causes Kevin to get revenge on Morgg.
...Nor Iron Bars a Cage
6 six later, Morgg replaces the Null Void prison guards with robots so that they do not know what he's up to. He uses the hallucinogenic crystals to make the Null Void prisoners to mine for the hallucinogen. Kevin later attempts to kill Morgg by dropping him of an elevator but the elevator is stopped by Gwen Tennyson. He was later presumably arrested by the Plumbers.