Voiced by: Gary Chalk
- The Leader: He's the one who calls the shots.
- No Name Given: The toy bios of all the other Joes give out their full name, while Lt. Stone's name is only given as "Stone".
Sgt. Robert Stephen Savage
Voiced by: Michael Dobson
- Fish out of Temporal Water: He's a soldier from the 1940's now living in the show's current time.
- Human Popsicle: He was frozen until he thawed out in today's time.
Ballistic/Eagle Eye (Albert Salviatti)
Voiced by: Brian Drummond
Black Dragon (Kang Chi Lee)
Voiced by: Tony Lung (season 1), Terry Klassen (season 2)
- Expy: While the Extreme line based their characters as Broad Strokes versions of various Joes, Black Dragon is just blatantly Snake Eyes. They're even both blonde! The only difference is, Black Dragon is NOT The Speechless.
- Race Lift: In a pretty spectacular manner, all things considered. He only appeared in one franchise and this happened to him. His bio establishes him as being Chinese, yet he has constantly been depicted as a blond-haired guy.
Freight (Omar Diesel)
Voiced by: Blu Mankuma
Harpoon (Jose Montalvo)
Voiced by: Francisco Trujillo
Voiced by: Randall Carpenter
- Action Girl: She's an active member of the team who can fight with the best of them.
- Deadpan Snarker: She's the most snarky and quippy of the Joes.Lt. Stone: "Here, take these with you. *hands Mayday a pair of crutches*"Mayday: "Oh yeah, thanks. I can work on my golf swings."
- The Smurfette Principle: She is the only female Joe in this series and the only recurring female character in the first season.
- Toyless Toyline Character: She never had a toy made for her.
Metal-Head (Matthew Hurley)
Voiced by: Matt Hill
- Musical Assassin: Metalhead has a gun that plays rock music as a weapon. It blows up the Mecha-Mooks with ease.
- The Power of Rock: He weaponizes rock music.
- Reverse Mole: In the series finale, he pretends to turn traitor in order to help bring down SKAR.
Voiced by: Blu Mankuma
- Heel–Face Turn: Was an agent of SKAR until his brother was killed by their experiments.
- Toyless Toyline Character: There is no toy of him.
SKAR (Soldiers for Kaos, Anarchy and Ruin)
Voiced by: Richard NewmanA ruthless masked terrorist in charge of the millitary wing of SKAR, he moonlights as Count Von Raini. the leader of a small european nation. Skilled, manipulative and a master of disguise.
"WE WILL BE VICTORIOUS!"
- Bad Boss: In the comic, he routinely kills his own troops, including for reasons as petty as someone accidentally touching him.
- Mean Boss: In the cartoon, he's not as actively malicious although he clearly cares little for the well-being of his troops. His Establishing Character Moment in the first episode is violently slapping down a SKAR soldier who accidentally called him Iron Klaw while he is still in his Count Von Rani guise.
- Bastard Understudy: The Dark Horse comic reveals he assassinated his predecessor, the Duchess of Mklavia.
- Big Bad: He is the main antagonist, being the leader of SKAR and all.
- Bruce Wayne Held Hostage
- Contrasting Sequel Antagonist: To the (cartoon) incarnation of Cobra Commander. Where Cobra Commander was not particularly fit and threatening, incompetent and frequently belittled and second-guessed by his henchmen, Iron Klaw is muscular and imposing, effective, and inspire fear in his minions.
- Large Ham: He tends to be loud and vigorous when he speaks.
- Karma Houdini Warranty: For most of the series, he avoids punishment for his crimes, but he's finally captured in the Grand Finale.
Inferno (Kidwell Pyre)
Voiced by: Ian James CorlettA pyromaniac with an irritating laugh and a bad sense of humor. Has a childlike mentality, regarding warfare as a game and the vehicles and weapons under his command as "toys".
- Ace Pilot: He's often seen piloting the Skystalker jet, and his Toy bios state his role in SKAR is "Jet Squadron leader", which is odd as there's nothing pilot-like about his design.
- Chuck Cunningham Syndrome: Is a recurring character in the first season of the cartoon but doesn't appear at all in the second, though a target dummy modeled after him does show up in "The Silencers" and he is mentioned by Rampage in "Wreckage: Revenge".
- Evil Has a Bad Sense of Humor: His first file card notes that he's a "notorious joker who's anything but funny".' "When is a runway no longer a runway? When it's BLOWN AWAY, ah-ha!''"
- Freudian Excuse: He was bullied by two rich kids when he was a child.
- Mad Bomber: In the comic's "From the Ashes" arc, Inferno bombed several U.S millitary bases, killing dozens of people, and targeted a funeral for his victims attended by the president of the U.S.
- Meaningful Name: He's a pyromaniac with the surname Pyre.
- Psychopathic Manchild: As it says in his above description, he sees warfare as a game and refers to his weapons as "toys".
Rampage (J. Remington III)
Voiced by: Colin MurdockAn arm dealer who turns into a green Hulk-like monster when irritated, he supplies SKAR with Mecha-Mooks and other weapons. He has sight on SKAR's leadership, but begrudgingly grovels under Iron Klaw's command until the right opportunity comes along.
- Berserk Button: Anything can aggravate Rampage if it escalates enough, but being bossed around will instantly set him off."NOBODY GIVES ME ORDERS!"
- Contrasting Sequel Antagonist: Rampage is in many ways similar to Destro from G.I. Joe: A Real American Hero. Both are businessmen who supply robots and devices to the bad guys and are the most recurring villain next to the main antagonist, both wear some kind of armor with integrated hand guns, and both are not afraid to voice their contempt for the main villain. However where Destro was cool and professional, Rampage is an unhinged, treacherous maniac.
- Depending on the Writer: Wheter the gun on his shoulder works as a chaingun or a rocket launcher varies by episodes.
- Large Ham: Yet another hammy villain. He especially hams it up when he's angry.
- Put on a Bus: The second season begins with him being arrested and he remains out of focus for a while.
- The Bus Came Back: He returns in "Rampage for President".
- The Starscream: Rampage is obessed with the idea of becoming leader of SKAR' and he undermines Iron Klaw by disobeying his orders and abandoning him when it looks like the Joes could get him. This comes back to bite him when he gets captured by the US Army and Iron Klaw refuses to free him.
- Toyless Toyline Character: A toy was going to be made for him, but the Extreme line was cancelled before it could be released.
- Villain with Good Publicity: In "Rampage for President", a SKAR backer notes that the public knows him as a dedicated philanthrope due to his arms-dealing venture being covered up.
- You Wouldn't Like Me When I'm Angry: When enraged, he turns into a freakish green monster.
Voiced by: Elizabeth Carol Savenkoff
- The Dragon: She is Iron Klaw's second-in-command.
Wreckage (Eric Alexander)
Voiced by: Dale WilsonA soldier who formely served with Freight. He was shot down during an unnamed war in South America and apparently into a grotesque cyborg by the Inter-Alliance.
- Genius Bruiser: He's got both brawn and brains.
- Heel–Face Turn: In "Wreckage: Revenge", he finally learns that Iron Klaw is responsible for making him a cyborg and even contemplates joining the Joes at the end of the episode.
- Token Good Teammate: He's the most noble member of SKAR.
- Toyless Toyline Character: He has no toy.
- Tragic Monster: he's a downed soldier turned into an hulking cyborg by Iron Klaw, and tricked into thinking that the Inter-Alliance is responsible for what happened to him.
- Wouldn't Hurt a Child: In the first episode, he states that he draws the line at harming children.