Ultraman is the kryptonian conqueror of Earth-3 and founding member of the Crime Syndicate of America.
A violent, homicidal megalomaniac, as well as an elitist and Darwinist who values strength and selfishness, and hates weakness and altruism, Ultraman is the Earth-3 version and moral opposite of New Earth's Superman.
Twenty-Five years ago, on the planet Krypton, Jor-Il and his wife Lara were believers in "survival of the strongest" and so, when their world was being destroyed by the Anti-Monitor, the pair sought out the planet's escape rockets and actively murdered anybody trying to escape so that their own infant son Kal-Il could escape the destruction as the strongest child of Krypton and be their best hope for revenge against the cosmic being. As the child was sent away from the doomed planet, Jor-Il, sickened by his son's weak baby form, warned his son to be "the strongest there is", or be "nothing at all".
Traveling toward the planet Earth, little Kal was inundated with his parents' ideology and moralizing, warning him to be the strongest possible being - eschewing all weakness both in himself and in others. His rocket came to a crash in Smallville, Kansas, right through the roof of the home of abusive husband Johnny Kent and his drug-addicted wife Martha.
Discovering the boy eating chunks of Kryptonite rock, the child's first act was to blast away Johnny's hand using heat vision, and then ordered them that they would be his parents from that point on. As "Clark Kent", he stayed with them until he was seven years old, when the couple tried to escape, he killed them and burned their farm to the ground.
Over the following years, Kal-Il took the name "Ultraman" and began his pursuits of taking over Earth by murdering the President of the United States Lee Harvey Oswald and forming the Crime Syndicate, manipulating the coward Harold Jordan into donning the Ring of Volthoom and becoming "Power Ring", and was in turn manipulated by the Amazon, Lois Lane into becoming her husband; a notion he agreed to on the agreement that she bear a child with him as the two strongest beings on the planet.
- He is fought as the final boss in Earth 3: The Panopticon.
- Along with Superwoman and Owlman, he is fought as a final boss in Earth 3: The Escape.
- Ultraman first appeared in Justice League of America #29 (1964).
- DC Universe Online's rendition of the Crime Syndicate of America and related materials is a mixture of their depictions in the JLA: Earth 2 and Forever Evil comic book storylines, as well as their appearance in the Justice League: Crisis on Two Earths (2010) animated movie.
- The Kryptonians of Earth-3 evolved to the point where they could gain great power from the radiation of their planet. The radioactive remains of Krypton give an even greater power to Ultraman who can absorb and process that radiation inside his own body to gain an immense array of abilities. The radiation of a yellow sun breaks down the Kryptonite radioactivity flourishing within a Earth-3 kryptonian's cells, eliminating their ultrahuman abilities while leaving them in a weakened and emaciated state.
- Superman has noted during a fight with Ultraman that Ultraman constantly murdering his opponents in their first confrontations actually made him weaker than Superman, as he simply eliminated his enemies upon encountering them as they were still getting used to their powers, while Superman fought them as they continued to get stronger and thus had to improve himself, putting Ultraman at a disadvantage when facing Superman's ability to think tactically.