Membership: Crawler, Leiko, the Light, Slider

Purpose: Conquering humanity and establishing mutant rule

Affiliations: Magneto (sought as a leader)

Enemies: non-mutant humanity

Base of Operations: The Galleria, Singapore; also a large ship off Singapore's coast

First Appearance: X-Men vs Avengers#4 (July, 1987)





History: The origins of the Underground are unknown, but they were gathered under the Light, presumably with the aid of Leiko, and sought to end the oppression of mutants by conquering humanity.

(X-Men vs Magneto#4) - As Magneto hid out in Singapore from a number of international superhumans, he was located by Leiko, who led Crawler and Slider to him. They convinced him to accompany them back to the Galleria, where the Light tested his identity and found it to be valid. They then named him as their champion and told him of their wishes to join him in the war against humanity. Then a military group broke in, hoping to capture Magneto, and opened fire on the Underground as soon as they realized they were mutants, too. Magneto easily decimated their attackers, and he followed the Underground to their ship base. There Magneto upgraded his helmet, using it to communicate with the Avengers and X-Men. His powers further amplified, Magneto teleported the heroes to his side and informed them of his plans to use the helmet to erase bigotry from the minds of humanity. After some argument, Magneto used the device on Captain America, but when he saw that it left him unchanged--meaning he had no prejudice in his mind--Magneto was shamed by his actions and surrendered to the heroes.

(X-Men vs Magneto#4 (fb) - BTS) - As Magneto appeared before a world court, those for and against mutants were whipped into a frenzy. A radical anti-mutant group located and attacked the Underground, who--without Magneto's might--were slaughtered.

(X-Men vs Magneto#4) - Magneto sent Captain Marvel (Monica Rambeau, now Photon) to summon Leiko to determine whether one of the chief justice of the world court, Du Motier, was a mutant. However, Monica found the Underground massacred, and Crawler told her what had happened. Leiko was among the dead
    Crawler and the Light, having survived the attack, watched as Magneto summoned his helmet to his side, hoping that he would use it to deliver vengeance for them. However, he only used it to erase the bigotry from the mind of Du Motier.

COMMENTS: Created by Tom DeFalco, Keith Pollard, and Josef Rubinstein.

No known connection to:

Crawler no known connection to:

The Light no known connection to:


Crawler accompanied Leiko and Slider to recruit Magneto. He was one of the few to survive the slaughter.

He can cling to surfaces


Leiko located Magneto and led Crawler and Slider to recruit him. She was slain in the slaughter

She could sense and track other mutants


Slider accompanied Crawler and Leiko to recruit Magneto. It is not known whether he survived the slaughter or not.

He can control friction, reducing it so as to make surfaces extremely slippery. It is not known whether he can increase friction as well.


--X-Men vs. Avengers#4








The Light


The leader of the Underground, he led them in their goal to overthrow humanity. He was one of the few to survive the slaughter.


--X-Men vs. Avengers#4







X-Men vs Avengers#4, p6, pan7

p6, pan 1;

p6, pan3;

p6, pan4;

First posted: 01/24/2004
Last updated: 05/30/2023

Any Additions/Corrections? please let me know.

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