Published July 14, 2023

The Official Marvel Guide to the Toxin Symbiote

Who is Toxin? Meet the heroic symbiote offspring of Carnage, who has bonded to Officer Patrick Mulligan and others.

The Marvel Universe is positively packed with dysfunctional super-powered families. Take Harry Osborn and his father Norman (AKA the Green Goblin), for example. There's also Tony Stark and his dad Howard, while Thanos killed his father Mentor. Bruce "The Incredible Hulk" Banner even fought his demonic dad in hell! The list goes on.

And yet, perhaps the most disturbing dynamic involves Marvel's earthbound symbiotes. It all started with Venom, of course, who first arrived on Earth after Marvel's original SECRET WARS (1984) event. But things got really bad when he gave birth to a seed that would become his son, Carnage, in AMAZING SPIDER-MAN (1963) #345 by David Michelinie and Mark Bagley, only for it to bond with a serial killer named Cletus Kasady.

Thus began a long and bloody war between the two, with each trying desperately to kill the other. As it turned out, this was just the way of the Klyntar (the real name for Marvel's symbiotes), wherein fathers hate sons and vice versa. Little did they know, however, that Carnage would follow in his father's black gooey footsteps by having his own child, quickly kicking off a brand new family feud that continues to this day.

Who Is Toxin: Son of Carnage?

Toxin—or the little globule that would become him—first appeared as a speck on the neck of police officer Patrick Mulligan in VENOM VS. CARNAGE (2004) #1 by Peter Milligan and Clayton Crain. When Mulligan responded to an explosion in New York, he didn't realize the blast was caused by Carnage trying to kill his spawn before it was born—an endeavor he failed to accomplish.

This new symbiote was officially named Toxin by his "grandfather" Venom in VENOM VS. CARNAGE (2004) #2 by Milligan and Crain. That same issue also showcases his fully-formed symbiote form when he finally bonds with Officer Mulligan during a fight with his father and grandpappy. 

During this fight, one thing became abundantly clear: as strong as Venom and Carnage are, Toxin is much, much stronger. As the 1000th symbiote born in the Venom family line, Toxin was destined for incredible feats, but he was also at risk of an even more severe mental collapse than Carnage's. 

While he was able to dispatch both Venom and Carnage with a little help from Spider-Man, the rest of Toxin's tumultuous early life didn't go well for either the symbiote or the law enforcement officer over whom it oozed. 

After accidentally bringing home a rotten human finger during his final fight against Carnage and Venom—and having to snatch it away from his suckling newborn's mouth—Mulligan realized he would be a constant danger to his wife Gina and his son Edward. In an effort to protect them, Mulligan decided to leave them, walking away from his life as an officer, husband, and father—and into the full-time toil of a symbiote host.

Years later, in TOXIN (2005) by Milligan and Darick Robertson, Mulligan resurfaced and joined Spider-Man's never-ending war against supervillainy. Specifically, Spidey tasked Toxin with confronting and containing Razorfist, an otherwise minor villain who had been recruiting impressionable youths into a blade-based cult. 

Since their first appearance, Mulligan and Toxin proved they had a tough time coexisting, fighting with each other as much as they did Razorfist and his crew. In the end, though, Toxin returned the flesh-flaying fiend to Ryker's Island. More importantly, Mulligan decided to reconnect with his wife, but unfortunately for him, his symbiote reveal was met with a hearty scream in a public restaurant. Admittedly, that probably wasn't the best place to introduce the two, though the embarrassment didn't encumber Mulligan for long. Then again, neither would his life.

Toxin Unbound: (Re)Enter Eddie Brock

Toxin reappeared in VENOM (2011) #12 by Rick Remender, Lan Medina, and Nelson Decastro, but only as the symbiote. Mulligan had been killed, and his costume captured by Blackheart, the son of Mephisto. This Stygian spawn used Toxin to create his own hellish hybrid: a heady mix of symbiotes and clones of Laura Kinney, then known as X-23. The Toxin costume was subsequently stolen by the truly vile Spider-Man villain Jack O'Lantern, who in turn gave it to his boss, Crime-Master. 

That's when things got especially bad.

In VENOM (2011) #17 by Remender, Cullen Bunn, and Kev Walker, Crime-Master revealed his true designs: to sell the Toxin symbiote to the highest bidder. However, fate intervened and offered Crime-Master a different path to plague the new "Agent" Venom, who, at the time, was bonded with Peter Parker's old friend, Eugene "Flash" Thompson. Instead of turning a profit, he wanted to create a new Toxin with the Venom symbiote's original host, Eddie Brock!

After losing the Venom symbiote, Brock waged a one-man war against crime… and symbiotes. Agent Venom quickly defeated Brock, who was left to hang dry in his webs—which is exactly where Jack and the Crime-Master found him. Forgetting their original scheme, they instead poured Toxin onto Brock and the two quickly bonded, much to Brock's initial chagrin.

Crime-Master enlisted the all-new, all-different Toxin into a team he called the Savage Six and got to business hunting Venom. During the fight that ensued, Venom set Brock and Toxin on fire, apparently killing both. This being the Marvel Universe, however, death is rarely the end—particularly when it involves symbiotes. 

Both Eddie Brock and Toxin reappeared, still bonded and still hunting Thompson, in VENOM (2011) #32 by Bunn and Declan Shalvey. Brock and Thompson beat the life out of each other before joining forces against a techno-organic hive of beings affectionately dubbed "The Symbiote Slayers." After defeating them, the symbiotes formed something of an understanding, if not an alliance: Brock's Toxin would leave Thompson alone unless he saw the Venom symbiote taking control. 

Brock, meanwhile, would use Toxin to return to his quasi-heroic roots and hit the streets protecting innocents like he originally tried to do as Venom. Unfortunately for him, this would lead once more to death—and even worse, Carnage!

Toxin & The Magical, Mystery Carnage

Like Agent Venom, Brock and Toxin were later conscripted, in this case by the FBI, for a mission to capture Cletus Kasady and the Carnage symbiote. Fitted with a remote-controlled inhibitor collar that kept Brock from accessing the symbiote—similar to the one used on Thompson's Venom—he and the team fell under hard times… literally, since the mines they intended to trap Carnage in collapsed.

Kasady, meanwhile, made friends with a cult he conveniently found underground, who saw him as a prophesied harbinger of their dead god, Chthon. As such, they meant to use the infamous Darkhold to bring said god back, starting in CARNAGE (2015) #4 by Gerry Conway and Mike Perkins. That turned out to be a bridge too far, and Brock's Toxin was finally set loose to fight.

He and another child of Carnage, Raze, fought an ultimately losing battle against Carnage, who used magic to beef up his own abilities and raise Chthon. In a last ditch effort, Toxin combined with Raze and another symbiote to create what can best be described as a divine being, who defeated Cthon and Carnage, killing the former and locking up the latter in a cage made of his own symbiote. 

Afterward, the Toxin symbiote made its way back to New York City to bond with a young, altruistic teenager named Bren Waters. Waters once again allowed Toxin to be purely heroic, as he was originally with Mulligan. This came in handy as he was once again thrust into a battle against his father.

Extreme Carnage: Toxin & the Symbiote Family War

Toxin was blissfully spared from the massive Marvel event KING IN BLACK, where the symbiote god Knull attempted to subjugate the planet and take over the universe. Unfortunately, he wasn't absolved of the aftermath. 

In the wake of that nightmare, during the EXTREME CARNAGE event, a group called the "Friends of Humanity" cropped up to speak out against alien invasions. The movement, helmed by a Senator Peter Krane and his seemingly reluctant son Arthur, led the charge to create safeguards against alien invasions, arguably at the cost of civil liberties for all Earth-dwellers.

In the end, Toxin teamed up with Flash Thompson—this time bonded with the symbiote "spinoff" Anti-Venom—and Venom's children Scream (who later became Silence, thanks to Anti-Venom's unique antibodies) and Sleeper. Their mission? To stop Carnage from fomenting national fear alongside the other symbiotes under his control—Phage, Riot, Lasher, and Agony—and causing mass panic and death. 

The ragtag team did successfully stop Carnage and his gang, but allowed the big red menace to get away with Agony. Worse still, Carnage hacked and hijacked Iron Man's strange extrembiote armor, which merged Stark tech with Klyntar biology. Still, Toxin was integral to ending the threat and proved he could be a force for good once more. 

Toxin is slated to return in VENOM (2021) #23 by Torunn Grønbekk and Ken Lashley for yet another fight against his grandpa, Venom. It's like they always say: "The more things change, the more symbiotes show up and cause toothy, gooey trouble." Thankfully for Marvel fans, Toxin is no exception!

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