Forever King

The Forever King is the leader of the Forever Knights. The first Forever King featured in the series was the fourth season's main antagonist. This Forever King was originally known as Driscoll, a former Plumber. However, he was thrown out of the Plumbers in disgrace when he was revealed to have been stealing alien technology for his own benefit. He later joined the Forever Knights and worked his way up the ranks, eventually becoming their leader. Driscoll first appeared in "Perfect Day" where he finds Enoch defeated by Ben. He then leaves Enoch after his multiple failures and decides to take care of Ben himself. He appears again in "Ben 10 vs. The Negative 10" where he rounds up a collection of Ben's old enemies to form a specialized team, in an effort to steal the Sub-Energy, a powerful energy source given to the Plumbers after capturing an alien convict. He eventually manages to steal it and enhances his armor suit with it. The energy source is eaten by Upchuck. His suit is destroyed, but Driscoll survives and escapes. At an unknown point and time, Driscoll was replaced, and a new Forever King was chosen.