|This article is about a/an group of monsters in Power Rangers Super Ninja Steel.|
The Gruesome Grunts were a mob of alien criminals who are wanted by the Halloween Intergalactic Court for their various crimes and the main villains of Monster Mix Up. They ambush the Super Ninja Steel Rangers and switch bodies with them. Unlike other villains in the series, they are not associated with Madame Odius or Galaxy Warriors, and in fact, declared that they would become even more famous than Odius by defeating the Power Rangers.
Versix and the others Gruesome Grunts ambushes the Rangers and switch bodies with them. The Mummy Guards arrive and take them all to the Halloween Intergalactic Court, except Brody (in Ackshun's body), Sarah (in Plasmora's body) and Versix who goes after them. After Mick Kanic posed as Versix to get a confession of the body-swapping plot, the Gruesome Grunts try to escape, which Verisx succeeds at doing, but the Court Witch apprehends the others with a freezing spell and the Pumpkin Judges ordered her to undo Versix's body-swapping spell. She does so and the Gruesome Grunts are destroyed by the Pumpkin Judges for their heinous crimes while the Rangers go after Versix.
He fought off the Rangers and survives all attempts to defeat him, including the Lion Fire Flame Strike and the Lion Fire Double Super Strike with the Superstar Blade, He then enlarges himself so the Rangers summon the Ninja Steel Ultrazord. He deflected the Ninja Ultra Strike and stamped the ground hard enough to tear it apart. The Rangers realised that he would break up any Megazord they formed so they called upon the Rumble Tusk, Astro, and Sub Surfer auxillary Zords. He tried to fight back but was overwhelmed by the combined might of the Zords and was destroyed by the Super Zord Slashes Final Attack (performed by the components of the Ninja Steel and Bull Rider Megazords). In his final seconds, he cursed not having gone trick or treating and then detonated, marking the end of the Gruesome Grunts,
- They are similar to the Galactic Ninjas, but they are more numerous, appeared in only one episode and are not allied with Madame Odius. Instead, they wanted to be more famous than her by outdoing her in defeating the Rangers.
- They can be considered as Madame Odius' rivals.
- Each member consists of different monsters:
- Two Power Rangers exclusive monsters who used recycled costumes from previous seasons (Shelldax and Plasmora).
- Two regular monsters of the week in Ninninger (Stabberous and Jabberon).
- A monster whose sentai counterpart was part of the Western Yokai (Fangore).
- A Kyoryuger monster that was unused in Dino Charge (Ackshun).
- A monster whose Sentai Counterpart was part of the Advanced Yokai ([[Versix).