Fan Casting Ultraman in Justice League: The Looking Glass

Just like Superman, Ultraman acted like a hero on his Earth, at least until the day that President Lex Luthor executed one of the members of the Justice League, John Stewart. Lex bragged that Superman never had the stomach to finish him off because he loved his glory. Affected by this, he responded by saying that if being a "hero" meant that, then he would cease to be one. Known eventually from that moment on as Ultraman, he used his heat vision to execute Lex, and reshape the team of 'heroes' that would now become the Justice Lords, by imposing his form of "peace" on Earth through strict rules. Now, he thinks he must spread his form of justice to this world as well.