Lord Nemesis

Lord Nemesis was the ruler of Earth-4, until Akuroninja killed him. He is one of the main villains of Kuroninja Gold.

History
Lord Nemesis was the ruler of Earth-4. He trained an army of evil rangers known as the Enforcers. They were supposed to be his army, but then Akuroninja killed him.

Later, Lord Nemesis ended up in Darkprism, but due to his power, they put him in solitary confinement. He then broke out eventually, with the help of two denizens of the Shadow Realm.

Trivia

 * Lord Nemesis is based on Lord Zedd, obviously.
 * This is one of the few times where there’s a counterpart to a Power Rangers character in another universe.