Luxaar

Luxaar, also known as "Grandmaster Luxaar", is the leader of the Ganglion and the main antagonist of Xenoblade Chronicles X. He is also a descendant of the Great One, the original pilot of the Vita, a skell that is later used by Luxaar to fight the party.

First appearance
Luxaar is not seen until Chapter 6, where Goetia reports back to him about the Human alliance with the Ma-non.

Planing the attack on NLA
Once the party has retrieved the Vita from the Tainted, he instructs Ga Jiarg and Ga Buidhe to retrieve it from New Los Angeles while Ryyz, Dagahn and a group of Ganglion members launch a diversion attack on the city. At the end of Chapter 8 he is given the Vita which was sucessfully retrieved from the attack, and addresses it as the skell of "The Great One".

The Wrothians' "Betrayal"
At the end of Chapter 9, Luxaar is contacted by Ga Jiarg when the Wrothians decide to abandon the Ganglion and refuse the protection that the Ganglion was giving to them.

The Zu Pharg menace
Luxaar is seen once again when Ryyz takes the Zu Pharg without his approval, he is shown to be infuriated by the fact that no one in the organization seems to respect the actual chain of command of the Ganglion.

The raid on the Lifehold Core
He is then seen again in Chapter 12, in which he orders the attack on the Lifehold Core before deciding to go down and destroy it itself with the Vita when he sees that the shields surrounding the Lifehold Core. He bursts through the wall of the Core and confronts the party, explaining that humans are the descendants of the Samaarians and that their DNA is what makes them so dangerous to the Ganglion, who were created artificially by the Samaarians and designed by them to be destroyed by it if they should turn against them.

Final Boss
When the Vita is defeated, it sinks into the pool below the Core and the party believes Luxaar dead - until he resurfaces and attempts to destroy the supercomputer containing the genetic information and memories of the remaining humans in a last attempt to definitely destroy humanity. He is stopped abruptly by Lao, who stabs him in the back with his spear. The two fall back into the pool, along with the Vita, and Luxaar dissolves in the DNA and fuse with Lao and the genetic information of every species found on earth, giving birth to the chimeric form of Lao.