Real Name: Timothy Halloran

Identity/Class: Extradimensional (Alternate Earth, Ultraverse), human mutate (Ultra)

Occupation: former student

Group Membership: None

Affiliations: Ultraforce (Black Knight, Ghoul, Prime, Prototype, Topaz), Foxfire; Dirk (mother's boyfriend);
Exiles (Catapult, Dr. Rachel Deming, Deadeye, Ghoul, Mustang, Tinsel), wished to aid and recruit him, but he mistook their intentions and fought them

Enemies: Bloodbath, Bruut, Malcolm Kort, Sludge

Known Relatives: mother (deceased)

Aliases: None

Base of Operations: San Diego, California; Visionary Productions, Los Angeles, California; EARTH-ULTRAVERSE

First Appearance: Exiles I#1 (Ultraverse) (August, 1993)



Powers: Halloran can transform into a large, elephantine-humanoid, with great strength (Class 25-75?) and durability. Apparently his intelligence began to degenerate sometime after his transformation, eventually leaving him as a bestial creature. As Mastodon, he has little control over his actions, and is a savage, cannibalistic creature. Mastodon retains some degree of Timothy's interests and memories.

History: (Exiles#1) - Timothy Halloran was a teenager living in San Diego with his single mother. Unbeknownst to him, he developed the Theta Virus, which made him a target sought by two people: Rachel Deming, who wished to help him, and Malcolm Kort, who wished to experiment on and learn from him. Deming and Kort each sent some of their agents to bring Halloran to him or her. Kort's agents overpowered Deming's and abducted Timothy--whose mother was killed during the struggle.

(Exiles#2) - Bloodbath brought Halloran to Kort's base, Visionary Productions, where Dr. Deeters began to attempt to control his powers. Halloran's powers were just beginning to surface, and Deeter's noted that he demonstrated the highest degree of virulence of the Theta Virus that he had ever seen. Deeters was unable to get control of the process and Halloran burst forth from the tank, full transformed into his Mastodon form, just as the Exiles (Deming's agents) arrived to rescue him.

(Exiles#3) - The Exiles tried to explain themselves to Halloran, but just like always, things degenerated into a brawl. Kort's agents came out and joined the fight, and Timothy took off as the two opposing forces battled. Deming and her Exiles tracked Halloran down, and after some more fighting, Deming nearly succeeded in convincing him of her intent. However, the sirens of incoming police made Halloran think she was just trying to stall him until the cops arrived, and so the fighting began anew. Halloran eventually escaped the Exiles, but the combination of the battle and a massive dose of tranquilizers took their toll, reverting him back to human form. His human form was much more severely affected by the tranks. As he staggered off, one of Kort's Cybernoids identified him and began to follow him.


(Exiles#4-BTS) - Dr. Deming wished to continue searching for Timmy, but Deadeye, in charge of field missions, overruled her, and the Exiles returned to their base. Visionary Productions was destroyed and Kort himself was killed as a result of actions of Ghoul, of the Exiles. This most likely terminated the activity of the Cybernoid following Timothy.


(Foxfire#2(fb)-BTS) - Terrified by recent events, Timothy fled into the sewers. Knowing he could protect himself as Mastodon, he returned to that form and stayed in that way. Eventually, however, Timothy's mind and control began to fade, and Mastodon degenerated into a savage creature. He survived by consuming anything he could find, including any animals or even people.

(Foxfire#1) - Foxfire was blamed for a series of murders. Searching for the perpetrator, she wandered the sewers of New York, where she found a den full of comic books and human bones. She was surprised by its occupant, Mastodon, who attacked her. Mastodon eventually got the better of her, but she was saved by Sludge, who fought off Mastodon.

(Foxfire#2) - Foxfire, joined by Ultraforce, tracked down Mastodon, who had torn Sludge's limbs off and stuffed him into a drainpipe. Mastodon attacked Foxfire and the Black Knight, easily taking out the Knight. Foxfire pursued him alone and since she was now prepared for the fight, she managed to subdue him. Timothy's mind finally reasserted itself, and he returned to human form and explained what had happened to him. The rest of Ultraforce then arrived, and Ghoul recognized him from their encounter while he was part of Dr. Deming's Exiles. Timothy was taken to the hospital, under maximum security.



Comments: Created by Steve Gerber, Tom Mason, Dave Olbrich, and Chris Ulm (writers) and Paul Pelletier (penciler).

Timothy was only referred to as Mastodon in a next issue blurb in the Exiles series. Three years later (real time), he was identified by that name in Foxfire#2.

Brush with the Marvel Universe: Dane Whitman, the Black Knight, was part of Ultraforce at the time they encountered Mastodon. He fought Mastodon directly.


  • Mastodon, aka Elefante, a member of Project X, who became extremely old and crippled when his age suppression factor failed, @ Wolverine II#61
  • Mastodon of the New Universe, Dave Landers, @ DP7#1

Other than the Black Knight (Dane Whitman), no other Ultraverse characters mentioned have any connection to any characters in the more mainstream Marvel Universe.

Exiles I#1 (August, 1993) - Steve Gerber, Tom Mason, Dave Olbrich & Chris Ulm (writers), Paul Pelletier (pencils), Ken Branch (inks), Chris Ulm (editor)
Exiles I#2 (September, 1993) - Steve Gerber (writer), R.R. Phipps (pencils), Ken Branch (inks), Chris Ulm (editor)
Exiles I#3 (October, 1993) - Steve Gerber (writer), R.R. Phipps (pencils), Scott Reed (inks), Chris Ulm (editor)
Exiles I#4 (November, 1993) - Steve Gerber (writer), R.R. Phipps (pencils), Dave Simons (inks), Chris Ulm (editor)
Foxfire#1 (February, 1996) - Ian Edginton & Dan Abnett (writers), Kevin West (pencils), Philip Moy & Bob Almond (inks), Scott Bernstein & Hank Kanalz (editors)
Foxfire#2 (March, 1996) - Ian Edginton & Dan Abnett (writers), Kevin West (pencils), Philip Moy & Bob Almond (inks), Phil Crain (editor)

First Posted: 06/30/2002
Last updated: 08/02/2002

Any Additions/Corrections? please let me know.

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