Lothor

Kiya Watanabe, also known as Lothor is an exiled evil ninja master. He arrived on Earth with an army of evil space ninjas (space aliens trained in the dark ninja arts) that he has gathered in space, intending to conquer the planet and destroy all the protecting ninja academies with their ninja masters, allowing him to become the ultimate dark ninja master.

His minions at this point include Zurgane, Choobo and his nieces, Marah and Kapri. Later, he would be joined by Vexacus, Motodrone and Shimazu. His foot soldiers were creatures called Kelzaks.

History
When the son of Sensei Kanoi Watanabe, Cameron Watanabe, traveled back in time to obtain a magical amulet, he learned that Lothor was actually born on Earth as Kiya Watanabe, the twin brother of Kanoi Watanabe and Cam's uncle. This plot twist explained why Lothor and Sensei Watanabe had both been played by the same actor.

Kiya had been a student at the Wind Ninja Academy, in the Earth Ninja category. Even at a young age, he craved power and secretly began practicing dark ninja magic. When a woman named Miko was inducted to the Academy with a mystical samurai pendant, he attempted to steal it, but was stopped by Cam, who took the pendant back to the future. For his crimes, he was banished from the Earth by his sensei and, in his rage, he forswore his family and ninja heritage and declared himself to be Lothor. In space, he continued his mad search for power.

He later took on his two nieces Marah and Kapri as apprentices at the urging of their parents. He found them to be very annoying, but kept them around because they were family - an odd sentiment for one that had so recently abandoned his family on Earth, possibly an attempt to fill the gap left in his life alone.

At one point, he put several teenage girls under a love spell. His plan was to create a television show that brainwashes people into adoring him as their ruler. However, his plan is thwarted by the Rangers.

Before his attack on Earth, Lothor had returned to Earth previously in secret, a violation of his former sensei's orders. His purpose on this visit is unknown, but while there, he killed the Bradleys, the adoptive parents of Hunter Bradley and Blake Bradley. These two were taken in by Sensei Omino and trained at the Thunder Ninja Academy, which, unfortunately, was the first place attacked by Lothor's army. He captured the Thunder Ninja students and Sensei Omino, and even managed to convince Hunter and Blake that the Wind Ninja's current sensei, Kanoi, was responsible for their adoptive parents' deaths.

The Wind Ninja Academy, now under the leadership of Sensei Kanoi Watanabe, Lothor's brother, was the next target. Once again, Lothor kidnapped the students of the academy, and with his magic, he turned Sensei Watanabe into a guinea pig.

During the series
Lothor's victory was short-lived, and he soon realized that three students had escaped the purge of the Wind Ninja Academy (Shane, Dustin, and Tori). Being the only three remaining, they were presented with morphers, allowing them to become Ninja Power Rangers. These new Power Rangers foiled Lothor's plans on numerous occasions, and he has sent monstrous warriors after them, but they all fail. Nevertheless, he has always stuck by the evil code for destroying a Power Ranger, that "they must be in their true Ranger form." Lothor has a campy sense of humor, which is often reflected from his frustrations with his monsters/nieces when they fail to best the Power Rangers, or in some predictable occasions (e.g. after making a monster grow, he stares at the camera and asks the audience if they really expected him to make it smaller.) Such fourth wall breaking manifested itself in several other of Lothor's asides (in the season finale, piloting the final giant robot the Rangers would fight, he comments on the battle was the most fun he'd had all season) as well. thumb|left|150px|Lothor being defeated and sealed into the Abyss of Evil Eventually, treason and betrayal among Lothor's generals led to them all dying off - at each other's hands or at the hands of the Power Rangers. It was soon revealed that these deaths had all been a part of Lothor's great plan: when each died, their spirits had gone to the "Abyss of Evil." With the help of Cam's stolen Samurai Amulet, Lothor was able to make the Abyss overflow and the dead generals and armies were all released once again, free to destroy the world. Shane was quickly able to destroy the resurrected generals with his Battlizer while the other Rangers tossed the other monsters back into the Abyss. Lothor then managed to use Cam's Samurai Amulet to drain the Rangers of their Ranger powers. Fortunately, Shane, Dustin and Tori were able to use their inner ninja powers to seal him and his deceased army in the Abyss of Evil, saving the planet.

Final Defeat
After escaping from the Abyss of Evil, Lothor allied himself with Mesogog. Capturing his brother and impersonating him, he brainwashed the three Wind Rangers into serving as his minions, in addition to releasing Zurgane and other monsters from the Abyss as well. However, the alliance between villains was defeated when Marah and Kapri, having forsaken the side of evil, freed Sensei Watanabe, who helped Cam and the Thunder Rangers recover their powers from the Abyss. The three Rangers then freed their brainwashed friends, and they teamed up with the Dino Rangers to battle the villains. When his plans failed, Mesogog turned on Lothor, using his psionic brain-blast to shrink him down to the size of an action figure, and trapped him in a jar as a trophy for his victory. The fate of the jar imprisoning him is never made clear, but it is possible that it, with Lothor still inside, was destroyed in the destruction of Mesogog's Island Fortress.

Alternate Lothor
In an alternate dimension, Tori Hanson met an alternate Lothor who is the Mayor of Blue Bay Harbor. His astrological sign is Libra. At first, Mayor Lothor didn't want to help Tori fight the Evil Ninja Rangers. When Tori was getting beaten by them, Mayor Lothor arrived with his group as well as some Kelzaks where they managed to defeat the Evil Ninja Rangers.

Powers and Abilities
Despite his exile from the Wind Ninja Academy, Lothor had grown to be a proficient master of martial arts. In addition to being an expert combatant, he also possessed superhuman strength. One example of this was during an altercation with his nephew Cam as the Green Samurai Ranger in Super Samurai mode. Lothor easily repelled his nephew's offensive strike with just one gesture of his hand. Lothor's main choice of attack was firing powerful lasers from the palm of his hands. This attack proved very effective against the Rangers in his ninja aerial attack. His laser was powerful enough to destroy Shane's Battlizer armor in just one strike. Unfortunately for Lothor, during his final battle against Mesogog, Lothor used his lasers against Mesogog twice in the battle (with the second time striking his opponent with a direct hit), only for Mesogog to be unfazed by the attack.