Imperious

Referring to himself as the Dark Wizard of the Underworld, Imperious sees magic as a way to grant his own selfish desires. He was formerly a friend of Mystics' named Calindor, he himself one of the Mystics in the Great Battle. Fed up of following Leanbow's teachings and corrupted by dark magic, he betrayed the others and tried to take Bowen to the Underworld. He battled Daggeron over the baby, resulting in both combatants being cursed and sealed in a cave. Nineteen years later after Morticon had been destroyed, Necrolai tricked the Rangers into breaking the seal and retrieved the mummified Calindor. The Master brought him back to life as the mummy-like Imperious to serve as the new leader of the Underworld, a role Imperious took an immediate liking to. Imperious was easily annoyed by Leelee's complaining, turning her into an insect. With the ability to summon and free monsters (including himself) from the Underworld, Imperious wasn't hindered by a focus on escaping the Underworld like Morticon was, and focused more on direct attacks on the civilians of Briarwood.

In "Long Ago," Imperious briefly reassumed his previous identity as Calindor to gain Udonna and the other Rangers' trust, intending to poison Udonna, frame Daggeron as the traitor and steal the Xenotome. Luckily, Clare worked out his true nature and found out from Phineas he was the traitor just in time to stop Imperious from poisoning Udonna, and Daggeron prevented him from stealing the Xenotome and rendering the Rangers powerless. After that, he began seeing Daggeron as a personal rival.

In "Ranger Down," he dared Koragg to fight without magic, relying on only his physical strength. Koragg agreed, and his magic was turned into a purple Mystic Morpher that was given to Necrolai. Unbeknownst to Koragg, this was just the first step in a much larger plan - to destroy the Master and rule the world on his own. In the next step of Imperious' plan, he released the four Barbarian Beasts. Warmax and Shrieker were sent to battle the Rangers first, wearing them down, while he secretly dispatched both Fightoe and 50-Below to take out Koragg so he couldn't interfere. Imperious then sent them to battle the Rangers, knowing that their laziness and battle fatigue would cause them to summon Jenji - at which point Fightoe captured him and took him to the Underworld, where Imperious used Jenji's power to wish for a world where good magic and everything related to it didn't exist, rendering the Rangers powerless. This allowed the forces of darkness to conquer the world - Rootcore was reduced to rubble and the Rock Porium vanished, color was nonexistent, humanity was enslaved and music was outlawed. One thing Imperious hadn't counted on was that Koragg had survived and plotted against them, helping the Rangers to reach the Tribunal of Magic and reverse Jenji's wish, after which 50-Below was destroyed. After the battle, Imperious scolded Fightoe for fleeing from battle and destroyed his body and then used Fightoe's soul to power the war machine monster, Ursus, which was also destroyed.

Imperious later attempted to convince the Master that Koragg was incompetent and a traitor in order to get rid of the warrior once more, but failed. Realizing he was unable to destroy the Master as long as Koragg was around and scared of his treachery being found out, he decided to get into the Master's good books instead by raising him out of the Underworld with the Ranger's Legend powers. To that end, he formulated a plan by separating Daggeron from the Rangers and destroying him, while using his power to create the Chimera to help drag the Rangers down into the Underworld; Udonna's interference and Koragg's transformation back into Leanbow freed the Rangers, but the Master was still rising. Imperious was on the verge of triumph when it was discovered Daggeron had in fact survived. Imperious challenged him to a bound battle - the two, in their Ancient Mystic Modes, would be chained together and fight with only swords. Imperious cheated, snatching the Solaris Laser Lamp for use and mocking the idea of fighting with honor. Despite this, Daggeron was able to win and mortally wounded his enemy. Imperious regressed back to Calindor and then into the mummified shell of himself before dissolving to dust as he made a cryptic remark about the coming of the Ten Terrors.

Imperious is a skilled fighter and extremely powerful, as well as supremely arrogant. He balances out his physical strength with magical powers, which is the same kind of magic as the Mystic Rangers' only to a higher degree, and he is willing to use forbidden magic (such as to create the Chimera) and can free banished monsters. He carries around a Folding fan that he also uses as a weapon as he can use it to send magical spells and it can also become a staff that can be used in battle. He can grow to a size more than one hundred times the size of the Titan Megazord. In his first encounter, he easily defeated the Rangers, and only Jenji's surprise attack and the fact his magic hadn't yet returned to full strength (due to being stuck in the cave) drove him back. Despite his new form, he can return to being Calindor at will and use his old Ancient Mystic Mode. In his Ancient Mystic Mode, he uses a Mystic Sword similar to the one that Daggeron uses and that both used during their final duel, and was able to fight him evenly matched, showing that he hadn't forgotten any of his old fighting skills.