ZüM is a White Martian and one of eight-such individuals who comprise the super-villain team known as the Hyperclan. Disguised as alleged "heroes" from another world, the Hyperclan sought to turn public opinion against Earth's super-hero populace, in particular, the JLA.
ZüM assumed the guise of a super-speedster, which was just one of the inherent powers available to him. ZüM and his teammates Armek and Zenturion fought against rookie Green Lantern Kyle Rayner and the Flash in the Gobi Desert. Flash and ZüM raced across Beijing and it appeared as if he were actually faster than the Flash. Although he did not derive power from the same Speed Force as Wally did, ZüM was able to execute strategic super-speed maneuvers such as vibrating through brick walls, accelerating the molecular speed of the wall, turning the individual fragments into mini-grenades. He also confounded the Flash's perceptions by generating after images of himself, modulating his frequency so that they appeared to exist in multiple locations simultaneously. The Flash ultimately caught up with ZüM in South Dakota. By pushing himself to near light speed velocity, the Flash was able to reach ZüM's destination before him and ambush him. Harnessing the infinite mass that light speed travel affords him, the Flash punched ZüM, sending his body hurtling across the planet. Because of this, ZüM was not present when the rest of the Hyperclan captured the Justice League and brought them to Z'onn Z'orr.
ZüM regrouped with Armek and followed him back to their headquarters, but by the time they arrived, the JLA had already escaped and had learned about the Hyperclan's Martian heritage. This time, ZüM traded blows against Aquaman, mistakenly believing him to be the weakest link on the team. Aquaman used his telepathy to affect ZüM's basil ganglia (inherited from a species marine ancestors) to give him a seizure, ultimately incapacitating him.
When the rest of the Hyperclan were defeated, the Martian Manhunter used his powers to wipe their minds and memories, forcing them to assume human forms. Providing them with new identities, he then sent them out to live as productive members of the human race.
ZüM had all the Martian powers, but he had the highest super-speed of all HyperClan members, almost rivaling that of Flash.
- Martian Physiology: The average Martian possesses the potential for the following power set:
- Shape-Shifting: Martians have psionic control of their physical for down to the molecular level. This allows them to a form of shape-shifting that allows them to mimic other forms, elongate aspects of their body, increase or decrease their physical size, and so on.
- Invisibility: Martians can cause the biopolymers in their bodies to lose their ability to reflect light, making the Martians invisible to normal light and human sight.
- Phasing: Martians can go through solid matter.
- Superhuman Durability
- Superhuman Strength
- Superhuman Stamina
- Extrasensory Input
- Super Hearing
- Martian Vision: Martian visual acuity greatly exceed human norms and allows for a wider range of information to be observed. This includes the following:
- Telepathy: Martians have the ability to read the minds of others and project their thoughts to varying degrees. They can also project their mental essences into a gestalt community known as the "Great Mind". Through this, the community can enhance the telepathic strength of other Martians. This power can also enable them to reverse the effects of amnesia or psychological brainwashing. 
- Astral Projection
- Mind Control: As an extension of this, Martians can also use the ability to alter a psychological profile of a target, enabling them to manipulate, and in some cases, outright control that individual. This practice is greatly discouraged however, and only rarely used. 
- Telepathic Relay
- Telepathic Assault
- Martian Physiology
- Vulnerability to Fire: Martians are much more vulnerable to fire than the average Earth human. At times this has been portrayed as physical, psychological, or a combination of the two. The effect of this is to strip any Martian of their powers as they involuntarily lose control of their body.
- 7 Appearances of ZüM (New Earth)
- 4 Images featuring ZüM (New Earth)
- Quotations by or about ZüM (New Earth)
- Character Gallery: ZüM (New Earth)
This character is or was primarily an enemy of the Justice League, in any of its various incarnations. This template will categorize articles that include it into the category "Justice League Villains."