|No. of episodes||
In it, the Crustaceans have replaced the Magnavores as the Beetleborgs' new arch-enemy. Nukus discovers that his creator is actually Art's incarcerated brother, Les Fortunes. Nukus busts Les out of prison. Les now serves him by creating new villains and monsters for him. In response, Art creates powers, armor, vehicles, and weapons, which Flabber then brings to life again for the kids, who rechristen themselves as Beetleborgs Metallix, hence the title. They are later assisted by the Astralborgs, four Beetleborgs created by Art Fortunes as a child when he and Les worked together on their only collaboration, the Lost Comic. Nukus formed his own evil group, named the Crustaceans. He would later recruit more faithful followers from the Lost Comic in the form of the Mantrons. Nukus and Vilor eventually gained upgraded Mega forms. To counteract this, the Beetleborgs were given an upgrade by Roboborg, who fused their Metallix powers with their original powers, creating the Mega Spectra Beetleborgs. Vilor's "mega" form did not last long and he quietly returned to his original look without explanation; however, Mega Nukus retained his upgraded look.</p>
The series concluded with the Beetleborgs gaining the enemy Boron as an ally, stripping Nukus of his greatest weapon; and Les Fortunes made the decision to return willingly to Charterville prison, disabling Nukus' ability to create new monsters out of illustrations. With no known way of returning the Crustaceans to the comic world, the Beetleborgs were left with an unresolved final battle with what was left of their foes.</p>
- Andrew "Drew" McCormick - the Chromium Gold Beetleborg in the second season, is the leader of the Beetleborgs. He was granted the ability of telekinesis by Flabber, which he activated by pointing at an object and nodding his head. Drew received an upgrade, Mega Blue Beetleborg, after he used the energy axis that powered Shadowborg on his original armor. After Roboborg arrived, Drew received a new upgrade, Mega Spectra Chromium Gold Beetleborg, after Nukus and Vilor went Mega themselves. His armor was modeled after a Japanese rhinoceros beetle. He was portrayed by Wesley Barker.
- Roland Williams - The Titanium Silver Beetleborg in the second season, his family owns a local comic book shop named Zoom Comics, where he, Jo, and Drew usually hang out. He was granted the ability of super speed by Flabber, which he activated by snapping his fingers. After Roboborg arrived, Roland received an upgrade, Mega Spectra Titanium Silver Beetleborg, after Nukus and Vilor went Mega themselves. His armor was modeled after a stag beetle. He was portrayed by Herbie Baez.
- Josephine "Jo" McCormick - the Platinum Purple Beetleborg in the second season, Drew's little sister, she was granted the ability of super strength by Flabber, which she activated by cracking her knuckles. After Roboborg arrived, Jo received an upgrade, Mega Spectra Platinum Purple Beetleborg, after Nukus and Vilor went Mega themselves. Her Red Striker armor was modeled after a flower beetle, and her Platinum Purple armor after a ladybug. She was originally portrayed by Shannon Chandler, and later Brittany Konarzewski. Jo is often shown wearing a baseball cap backwards.
- Astralborgs: Four heroes of the Lost Comic.
- Dragonborg (voiced by Doug Stone impersonating Sean Connery): Modeled after a dragonfly, leader of the Astralborgs.
- Fireborg (voiced by Gene Holliday): Modeled after a firefly.
- Lightingborg (voiced by Richard Epcar): Modeled after a cicada.
- Ladyborg (voiced by Barbara Goodson): Modeled after a butterfly.
- Hillhurst Inhabitants
- Flabber (Billy Forester): As described above, Flabber is a phantasm (phasm) who was trapped inside a pipe organ, and was freed by the kids. Out of gratitude he granted their wish to become their comic book heroes, the Big Bad Beetleborgs. This event also unintentionally released the Magnavores. Flabber was released by playing 3 notes (And later revealed that playing those same 3 notes, then playing them in reverse would again trap him inside the organ). He acts as an advisor and best friend, he offers needed magic to the kids when fighting the Magnavores, and later the Crustaceans. Although his magic doesn't always work the way he would hope for it to. He is the head of the Hillhurst Mansion and is usually the one to keep the house monsters in check. The producers of the show said that he was based on Elvis Presley.
- Mums (played by Blake Torney, voiced first by Michael Sorich and later by Torney): Mums is a 5,000 year-old Egyptian mummy, but he can unwrap his bandages to reveal a "Grim Reaper"-like form under his bandages. He has 703 brothers and sisters. In one episode, two archaeologists came to return Mums to the crypt in which they found him in order to get rid of a curse placed on them.
- Frankenbeans (David Fletcher): Called "Frankie" for short, he is a strange, lumbering Frankenstein's monster-type monster. He was once kidnapped by the Magnavores, and held by ransom in exchange for the Beetleborgs' Beetle Bonders. He allows Wolfie to stay in a dog house kept in his room. He has little ability to speak, often roaring or saying toddler-like sentences. Dr. Baron von Frankenbeans, his creator, showed up in a few episodes, a mad scientist who treated the monsters like servants. Whenever he announced his full name, he would be spotlighted by moonlight as lightning would flash and a wolf would howl outside (even if it was daylight).
- Count Fangula (Joe Hackett): Loosely modeled after Count Dracula, Count Fangula is a vampire (albeit one of questionable aptitude in the Dark Arts). He seems to be the only one to understand what Wolfie is ever saying. He once succeeded into getting two victimes in Van and Trip, temporarily turning them into vampires that were turned back to normal by kisses from Jo. If his victims quota is too low, a high ranking vampire will come to evaluate him.
- Ghoulum (voiced by Dan Letlow for one episode only): A living stone statue type monster that resides in Hillhurst Mansion who often had little to say or do other than what statues do best, stand in place. While not the most active monster of Hillhurst Mansion on rare occasions he would join in on the other monsters' mischief. In one episode, he was accidentally exposed to a 'Bad Potion' turning him evil and causing him to grow into a giant under Noxic's control.
- Wolfgang "Wolfie" Smith (Frank Tahoe, voiced by Michael Sorich, later Scott Page-Pagter): Wolfie is a werewolf and is treated more like a family dog than a monster at Hillhurst. His voice sounds similar to Astro and Scooby-Doo. Only Fangula can translate what Wolfie is saying most of the time. Probably the bravest and most cunning of the Hillhurst Monsters because he's the only one of the group who tangled with the bad guys at least once.
- Little Ghoul (Lina Godouse): A Jawa-like ghoul who was the latest addition to the Hillhurst group in season two. She lives in the basement and rarely comes out. A niece of the Grim Reaper, she is a grim reaper-in-training who loves collecting. She also has a short temper, which scares the other monsters even more than her true appearance under her hood. She has little to no respect for anyone; she does, however, have a great deal of respect for the Astralborgs. In one episode, she possessed a head that originally belonged to the Headless Horseman.
- Arthur "Art" Fortunes (Rigg Kennedy): Creator of the Beetleborgs' comics, who shows up time and time again with new ways to help the kids. He often collaborates with Flabber's magic to bring new arsenal to the kids.
- "Nano" Williams (Vivian Smallwood): Roland's grandmother, Aaron's mother, and Abbie's mother-in-law, Nano is one hip granny and a trained martial artist. When she's not running Zoom Comics, or practicing her moves, she's often seen riding her motorcycle. Nano often helps out the kids when they're in a jam. If nothing else, she enjoys teasing her son Aaron.
- 'Crustaceans' (52-88): Villains created by Les Fortunes, the second set of villains the Beetleborgs faced.
- Nukus (Christopher Cho) (52-81): A creation of Les Fortunes, the Triceratops-based Overlord of the 2nd Dimension. Hid away in Art Fortune's vault until the Magnavores took the picture and Vexor brought him to life. Nukus quickly set a plan to dispose the Magnavores and take over as the new villain. He broke Les out of jail to use the artist's skills to create deadly monsters that could be brought to life with the use of his sword. He had an advantage over the Beetleborgs as he destroyed both the paper he came out of and the copy Art Fortunes owned. Nukus also destroyed the Beetleborgs' original armor, weapons, and powers. He later gained a mega form, Mega Nukus (81-88), from touching Les Fortunes' transmographier device which he destroyed soon after to ensure no one else received an upgrade from it.
- Horribelle (Claudine Barros) (54-88): Second-in-command of the Crustaceans, an insect-based sword-toting fighter and Nukus' right-hand woman. Like Nukus, she can summon a face-mask in battle. She also wields two swords that resemble mantis arms. She once rebelled against the Crustaceans by having Les Fortunes create the Astral Axe, so she could control its powers out of a scorn for not receiving a mega form like the main male villains.
- Vilor (played by Kyle Jordan and voiced by Dave "Foots" Footman) (54-88): Third in command of the Crustaceans, a fish-based, trident-toting fighter. He briefly gains a second form, Super Vilor (76), when the Mantrons arrived, and later a brief mega form, Mega Vilor (81), after touching Les Fortunes' transmographier device prior to its destruction, though he somehow reverted back to his normal state.
- Lester "Les" Fortunes (Marshal Hilton) (54-88): The black sheep in the Fortunes family, and Art's older brother. He was in jail when Nukus recruited him to his cause. Despite creating all the Crustacean monsters and their arsenal, Les never gets any respect or credit for it. At the end of the series, he goes back to jail for some peace and quiet.
- Mantrons (75-82): Evil counterparts of the Astralborgs. Created by Les Fortunes as a child to rival Art Fortunes' Astralborgs in their only collaboration, the Lost Comic. They were there to aid Nukus in his plans to get Roboborg, who ultimately made it to the good hands of the Beetleborgs. In 'Roboborg' (part 8 of the Lost Comic saga), the Mantrons were finally sent back to the Lost Comic for good by the combined attacks of the Beetleborgs, Astralborgs and Roboborg.
- Dregs (55-88): Assorted monsters used as foot soldiers. Dregs came in two groups. One group was based on land animals and wore brown slacks and black boots (Spider Dreg, Stego Dreg). The other based on sea creatures and wore blue spandex pants and white boots (Fish Dreg, Jellyfish Dreg, Squid Dreg). Each group consisted of five different types of Dregs.
- Worm Tanks (55-88): Giant worm like vehicles summoned to attack the Beetleborgs on several occasions.
- Crustacean Jet Fighters (56-88): Air-borne machines based on the design of the Worm Tank summoned to attack the Beetleborgs on several occasions.