Ta'aun, Hand of Oryx
Ta'aun, Hand of Oryx was once Primus Ta'aun, the commander of the Cabal Sky Burners, and bonded with the Shield Brothers Valus Tlu'urn and Valus Mau'ual. When the Taken first arrived at Phobos, Ta'aun gave the order to evacuate Fleetbase Korus. He filed a report on the ineffectiveness of his forces against the Guardians, and suggested that the technology aboard Oryx's Dreadnaught might be co-opted by the Cabal to nullify Guardian Ghost regeneration. This report was sent up the chain of command to the Emperor himself, who ordered Ta'aun to personally board and capture the Dreadnaught by any means necessary. After the Awoken armada was destroyed by the Dreadnaught's main weapon in the Battle of Saturn, Ta'aun rammed his warship, Dantalion Exodus VI, into the Hive vessel to land his troops. In the Story mission Enemy of My Enemy, Ta'aun was Taken while attempting to reach the rupture in Mausoleum that led to the realm of Oryx, and was turned into Ta'aun, Hand of Oryx Ta'aun returns in the mission Regicide alongside Baxx, Hand of Oryx to bar the Guardian's path to Oryx himself.
Gameplay
Primus Ta'aun is first seen in the story mission Enemy of my Enemy, where he is seen leading his attack force in a battle against the Hive to get to the rupture. He tries to mow down incoming foes with his heavy weapons, but becomes Taken and turns into Ta'aun, Hand of Oryx in the story mission Regicide. He fights alongside Baxx, Hand of Oryx to keep the Guardian out of the portal that leads to Oryx's altar. In battle, his Heavy Slug Thrower retains the deadly power and accuracy of those of regular Colossi, and although he cannot fire missile swarms, he can still hammer the player with long range suppressive fire. If Baxx is killed first, Ta'aun will go "berserk" and chase the Guardian until it can either land a hit with his ground smash or is killed himself.
Trivia
Ghost and Cayde-6 refer to Primus Ta'aun as a "Centurion" during Enemy of My Enemy, but Ta'aun is clearly a Colossus as he wields a Heavy Slug Thrower, a Cabal weapon used exclusively by Colossi. As Ta'aun, Hand of Oryx in Regicide, his weapon still functions identically to a Heavy Slug Thrower despite its visibly different Hive design. "Centurion" may simply be the catch-all term for a Cabal commander, with Colossi simply being larger, more heavily-armed Centurions.