Gloomius Maximus is a recurring character in the Rolie Polie Olie franchise. He is a pirate that lives in space and is the former arch-nemesis of Space Boy and Space Dog, Willy and Wally Jolly. Eventually, he befriended Olie, Zowie, and Billy, after getting his Happy Gear to work after Zowie's act of kindness. He is the leader of the The baddies who support Gloomius in his scheme to un-remunerate the universe. He is the main antagonist of The Great Defender of Fun (before he redeems himself in the end) and is one of the tritagonists of The Baby Bot Chase. He is also a minor character in the series.
Gloomius Maximus looks as though he had parts that came straight from a junkyard. His head has a blue paint job and appears to be rusting around his face. He has white eyes with black pupils, a dark green nose with a square in front of it, red lips, and two big sets of teeth inside his mouth. He wears a red pirate outfit, a golden belt with the letter G on it, a red bicorn hat with a feather on it, a single black boot on his left foot and has a brass sword-like appendage for a left hand and a brass peg leg replacing his right leg.
Originally, Gloomius hated anything fun and happy in general. According to what he told Zowie, this was because he never had a birthday party of his own as a little bot nor was he ever invited to one. So he decided that if he cannot be happy, no one can.
Gloomius began to use his un-funerators to suck the happiness and fun out of any bot, object, and planet he encountered. His arsenal of un-fun weaponry include his Ultra Gloomerator green puppy Glum Beam, capable of rendering a person "downer than the downy dumps" and fall asleep and unable to wake up. Only the power of laughter is capable of undoing the effects and sending him into retreating. Like all pirate stereotypes, he took anything that was not his, such as Zowie's Super Silly Ray in his first appearance. He used to hate laughter (his former only weakness) as it forced him to retreat.
He is very ticklish as seen when he burst out laughing when the Jollies used their swords to tickle him and when Olie threw a Tickle-Me-Pickle at him. He was immune to such fun weapons as the Super Silly Ray due to his extremely bad mood, but after giving it a tune up, Olie is able to blast a billion bubbles at him and he finally started to feel its effects and acted jovial and giddy. After getting his happy gear running for the first time in so many years due to Olie using the Super Silly Ray and Zowie's act of kindness of inviting him to her birthday party, he became a completely different bot all together, declaring, "I'm the happiest bot in the universe!".
Afterwards, Gloomius has become a mischievous, fun-loving character and values Zowie as his best friend.
- Gloomius Maximus is a play on the words "gluteus maximus", the main exterior muscle of the hip.
- He appears as the Big Bad of The Great Defender of Fun and the Lancer to Olie Polie and Zowie Polie in The Baby Bot Chase.