Ultra Elites are field commanders in Halo but they lead lower ranked Elites into battle in Rise of the Spartans. Usually they would wield Gravity Hammers or sometimes Heavy Weaponry and Energy Swords. Ultras command armies or even small armies into battle, and are known as extremly aggressive in the machinima.
Once the Elites broke out the door and fought against the UNSC forces, an Ultra Elite faced off against Ocelot. After missing many swings against his oppoment, the Ultra finally knocked Ocelot down with his energy sword. But Ocelot got back up and killed the Ultra with his shotgun.
Stealing the AI
A small army of Elites with Wraiths arrived at the AI's location and an Ultra was in front of the small army with his Gravity Hammer as it's leader. Swift found Whisper ordering her to fight the Elites and he'll go after the AI.
Kalos stole the AI and Swift shot at him but failed to kill him, Kalos went upstairs in the base and the Ultra appeared up the stairs with Kalos. The Ultra went down to fight Swift while Kalos escaped and aggressively knocked the boxes with his hammer to find Swift. Although through a small battle, Swift smashed through the window behind the Elite and assassinated him.