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Official Site: Marvel

Ultimaton, also known as Weapon XV, is a living weapon created by the anti-mutant supersoldier program Weapon Plus. The character was created by Grant Morrison and Chris Bachalo, first appeared in New X-Men #143 (August 2003). Ultimaton escapes from the Weapon Plus facilities, fights the X-Men and is destroyed. He is later resurrected to guard a child clone of Apocalypse.

Ultimus (Ard-Con) was created by Gerry Conway and John Buscema, making his debut in Thor #209 as Demon Druid, while he made his debut as Ultimus in Wonder Man #7.

The Kree known as Ard-Con was a member of the Kree Eternal sub-race created by the Celestials. He with the other Kree Eternals travelled through space, eventually, coming across Earth 4000 years ago. The Celts of Earth mistook the Kree Eternals as deities and soon all Kree Eternals left Earth except Ard-Con who stayed on Earth for a millennium, but was then imprisoned by the Deviant, Tantalus. He also encountered Odin once, claiming that his name brought back memories, but also thought that Odin had died. He was then accidentally freed by Thor when the latter used mjolnir to turn into Donald Blake. Once free, he started wreaking havoc across the streets and knocked Thor unconscious. He was then apprehended by the British Army and Thor again, but stopped fighting when Thor realised that Ard-Con was trying to reach a portal at Stonehenge in order to depart Earth. After that, Ard-Con successfully departed Earth.

Ard-Con was unable to find his people so returned to Earth thanks to a portal created by two tourists and the hero Meggan, who were under the influence of the Eternal. Shadowcat intervened and freed Meggan along with tourists and also allowing Rachel Summers getting some knowledge about his people. Ard-Con then broke into Darkmoor Nuclear Research Facility where he recreated a nuclear facsimile in order to use it at the Stonehenge and finally reunite with his people. However, the Excalibur intervened and stopped Captain Britain from fighting Ard-Con, while Kitty opened a portal to Ard-Con's people and apologized to him. This proved to be successful, however, upon arriving to his home, he was approached by the Supreme Intelligence who informed Ard-Con that he was the last surviving Kree Eternal. Then Ultimus, under the order of the Supremor, joined the Starforce.

Ultragirl has not been a contender in any CBUB matches.