Morticon Mortion is the dark leader of the undead. He is a creature that is part machine, which is powered by moving gears. He is so powerful that it makes it difficult for him to summon his power to the surface world. He uses a mystical portal that allows him to keep an eye on things and communicate with the master. He was ultimately destroyed by the Power Rangers.

Imperious Imperious takes over after Morticon is destroyed. He was once known as Calindor who betrayed the Mystics in the great battle. After a battle with Daggeron, he found himself cursed until Necrolai found him in a cave years later. He dared Koragg to give up his magical powers temporarily to prove his worthiness in battle. He challanged Daggeron to a duel, even though he did cheat by teleporting Jenji in his hand when Daggeron was going to send his final blow, he was still destroyed.

Koragg Koragg is the Knight Wolf who fights faithfully for the Master, but doesn't bow to anyone else. Although he is evil, Koragg insists that honor is the only way. He controls the powerful dark horse Catastros which is his faithful servant. Koragg has a mental link with Nick, communicating to the ranger through his mind. Koragg discovers his true identity - Leanbow and shortly after is released from the Master's hold.

Necrolai Necrolai is the vicious and unrelentingly Queen of the Vampires, who can fly to and from the surface world through the gate. She decives Koragg from time to time when asked to, such as puncturing him with an arrow and attaching one of Sculpin's scales to track his whereabouts. She has a human daughter named Leelee whose father's identity is unknown. Necrolai might get carried away with pleasing the Master, that she ignores her daughter but when Itassis was going to unleash her wrath, Necorali pleaded her to spare Leelee. She has the power to revive individuals such as Itassis. It was her daughter's confidence in her that caused her to revive Daggeron and Leanbow that caused her to become human.

Hidiacs Hidiacs are the zombie foot soldiers that serve the evil forces that threaten the planet. They carry axes into battle and beneath their masks is a rotted skull covered in worms. As undead warriors, they fight mindlessly for the will of their undead generals.

Styxoid The Styxoids are a higher evolved form of the Hidiacs. As leaders of the Hidiac army, the Styxoids carry spear like weapons into battle.