Emperor Gruumm

Emperor Gruumm (portrayed by Rene Naufahu) is a figurehead who serves as the de jure leader of the Troobians alien race whose ultimate goal is to conquer other worlds. Gruumm is relentless and nothing will stand in his way to conquer the universe. He previously destroyed the planet Sirius (home world of Commander Anubis "Doggie" Cruger]]), and in 2025 he launched an assault on Earth.

Gruumm's main strategy is to overwhelm and devastate a planet with constant, large-scale assaults and then drain the planet of its resources, as shown in the flashbacks to the Sirian invasion, and used such tactics on the Helix Nebula simply to draw the A-Squad into an ambush. His highly destructive tactics show life means little to him, and it was initially unclear why he wasn't using such tactics to conquer Earth except on rare occasions, and why he allowed Broodwing to battle the Rangers for him on several occasions. It's briefly shown that his ship can even destroy a planet from orbit. He also was shown repeatedly talking to either himself or an unseen entity whom he referred to as "the Magnificence". It became clear later on that Gruumm had been working off a long term plan, intending not to leech and destroy Earth but instead to use its resources - which he looted over the course of the season - to construct a body for Omni, a higher power who he fears and worships.

Emperor Gruumm has two aides, Mora (later Morgana) and Broodwing. He has a bitter hatred for Cruger, who cut off his right horn in the battle for Sirius. He is also the most powerful warrior among the Troobian empire, as proved in his victories over the B-Squad Rangers and Supreme Commander Fowler Birdie. His main weapon is a staff that shoots energy, and he also rides a motorcycle with laser cannons. Gruumm has the ability to use telepathy and shapeshift into a selected human form. In battle, he has shown the ability to decimate the Rangers, defeat Commander Birdie and also harm Zeltrax, though Cruger has shown the ability to defeat him.

As Omni's master plan came to fruition, Cruger escaped from a cell onboard Gruumm's ship and the two engaged in battle. Although Gruumm was thought to have perished along with the Magnificence, he survived and engaged Cruger (who was unmorphed) one last time, only to get his left horn cut off after being easily defeated. He was then contained. He appears in the Nintendo DS version of Power Rangers: Super Legends as the main villain who has set his sights upon the myth of the Hall of Legends, the resting place of the collected energies of Power Rangers across time. In his twisted mind he envisioned a world where his enemy's power is not only stolen, but used to make him a living god over all creation.