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Real Name: Inapplicable

Identity/Class: Octopus mutate

Occupation: Inapplicable

Group Membership: None

Affiliations: Kid Kaiju (Kei Kawade);
temporarily Abominable Snowman, Blip, Bruttu, Crawling Creature, Creature from Krogarr, Creature from the Black Bog, Fin Fan Foom, Googam, Goom, Gorgilla, Green Thing, Insect Man, It the Living Colossus, Klagg, Kraa, Metallo, Monsteroso, Monstrom, Moomba, Oog, Orrgo, Pildorr the Plunderer, Quogg, Rommbu, Sporr, Thing that Crawled by Night, Tim Boo Ba, Ulvar, Vandoom's Monster, Zetora, Zzutak

Enemies: Mark Faraday, Leviathon Tide, humankind (in general)

Known Relatives: None

Aliases: None

Base of Operations: Mobile in the oceans of eastern Europe

First Appearance: Tales of Suspense I#8/1 (March, 1960)

Powers/Abilities: Monstro was an ordinary octopus that was altered by the effects of radiation. Its size and proportionate strength were temporarily increased to perhaps 1,000 times normal (see comments).


(Tales of Suspense I#8/1) -The mysterious origin of the mutated octopus is unknown (see comments). The colossal creature first made its presence known when it lashed out with its enormous tentacles and destroyed the seaport of a small nation behind the Iron Curtain. The people of the area dubbed the behemoth "Monstro". Having no means to stop the super-sized cephalopod (...short of dropping an atomic bomb on it, which would only cause more destruction), the Soviets contacted Washington, D.C. with a request for help. In an effort to improve international relations, the U.S. State Department complied and enlisted the aid of Professor Faraday. The scientist flew to the Communist nation and witnessed another attack by Monstro. Faraday donned his scuba-diving gear and rowed a boat near the creature's location to investigate. Carrying a waterproof Geiger counter, the scientist dived into the sea and swam to Monstro, then took a reading with the device. When the creature caught sight of him, Faraday returned to the surface and frantically rowed back to shore, as Monstro rose from the churning waters and came after him. The scientist made it to safety, narrowly avoiding the crushing sweep of the creature's titanic tentacle. Faraday then reported to the Soviet officials that there was nothing they could do about Monstro--he only recommended that they should leave it alone and it would bother them no more after 24 hours. But the citizenry became unruly because the American seemed to do nothing to help them. That night, as the creature destroyed a building near the shore, Faraday used Monstro's onslaught as a distraction and made his escape from the hotel where he was staying, then he stowed away on a freighter bound for America, yet he was confident that the threat of Monstro would soon end.

    Twelve days later, Faraday was back in the United States. He met with a government official in Washington, who informed the scientist that the gigantic octopus had returned to its normal size 24 hours after Faraday examined it. Faraday explained that when he used the Geiger counter, he found Monstro to be radioactive--he surmised that the Reds had probably been conducting secret atomic weapons tests in the ocean, and that Monstro had been exposed to the radioactive fallout, which would account for the creature's freakish growth. Faraday also mentioned that he had calculated the radiation would wear off Monstro because the creature was no longer in the contaminated area--he didn't want to reveal any of his findings to the Commies because he feared they would have destroyed both the seaport and Monstro with an atomic bomb, rather than admit they were testing nuclear weapons.


(Monsters Unleashed II#2) - The Inhuman Kid Kaiju summoned Monstro along with numerous other monsters to an area outside San Diego, California in defense against the Leviathons.

(Monsters Unleashed II#3) - Monstro joined the fight against the Leviathons. Earth's heroes watched the monsters summoned by Kid Kaiju defeat the Leviathons. After the battle Monstro and the other monsters were teleported back from where they came.

Comments: Created by an uncredited writer, Jack Kirby (pencils) and Dick Ayers (inks).

There were no story panels that showed a complete view of Monstro, so I'm only making a very rough guesstimate as to how big it really was. 

In regards to Monstro's origin: It was never confirmed exactly what the source of its mutation was, and Faraday's theory of Soviet nuclear testing was merely his conjecture; but in the Monster Hunters storyline in Marvel Universe #'s 4 - 7, it was revealed that Warlord Kro of the Deviants was responsible for some of the monsters that menaced the world around this time-period, so maybe Monstro was his "baby". 

The creature was dubbed the "Menace From the Murky Depths" in the story title, so this could be considered an alias.

With his graying temples and smoking a pipe, I think Professor Faraday had a slight resemblance to Reed Richards. 

This story may have been "inspired" by the 1955 sci-fi film "It Came From Beneath the Sea". 

For more info on real octopi, see HERE

And a BIG Thank You to Monsterblog for the scans! 

Destroying the seaport and Monstro with an atomic bomb would only release more radiation, unleashing potentially more mutates. Perhaps it was a specific radiation (gamma?). But I still like the idea of Kro's "baby".
---Grendel Prime

In the story "Octopus" in Strange Tales I#55 (February, 1957) another mutated, giant octopus also mutated by radiation.

Profile by John Kaminski.

Updated by Markus Raymond (Monsters Unleashed).

Monstro has no known connections to:

Professor Mark Faraday has no known connections to:

Professor Mark Faraday

An American marine biologist, Professor Mark Faraday was said to be the foremost authority on ocean life. While working in his lab at an aquarium, he received a phone call from the U.S. government, requesting his aid for a Soviet nation that was menaced by a gigantic octopus. In the course of his investigation, Faraday went scuba diving near the creature and used a Geiger counter to determine the monster was radioactive. He correctly theorized that the radiation would soon wear off and the octopus would shrink back to normal.


--Tales of Suspense I#8/1

images: (without ads)
Tales of Suspense I#8/1, p1, pan3 (main image)
Tales of Suspense I#8/1, p5, pan4 (Monstro destroying building)
Tales of Suspense I#8/1, p3, pan2 (Faraday smoking pipe)
Tales of Suspense I#8/1, p4, pan3 (Faraday in scuba gear, carrying Geiger counter)

Tales of Suspense I#8/1 (March, 1960) - Jack Kirby (pencils), Dick Ayers (inks), Stan Lee (editor)
Monsters Unleashed II#2 (April, 2017) - Cullen Bunn (writer), Greg Land (pencils), Jay Leisten (inks), Mark Paniccia (editor)
Monsters Unleashed II#3 (April, 2017) - Cullen Bunn (writer), Leinil Francis Yu (pencils), Gerry Alanguilan & Michael Jason Paz (inks), Mark Paniccia (editor)

First Posted: 11/26/2010
Last updated: 04/13/2019

Any Additions/Corrections? please let me know.

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