Xol, Will of the Thousands
This article is about the Worm God. For the Story mission, see Will of the Thousands.
Xol, Will of the Thousands is one of the five Worm Gods, ancient beings second only to the Darkness itself in the hierarchy of the Hive pantheon. He is worshipped by the Grasp of Nokris, and is the main antagonist of the Warmind expansion. 
The Ancient Past
Xol was one of the five Worm Gods trapped beneath Fundament by the Leviathan, who helped orchestrate the rise of Oryx, the Taken King, Savathûn, the Witch-Queen, and Xivu Arath, God of War, and the corruption of the Hive precursor race. After Oryx slew Akka, the Worm of Secrets, Xol began to fear that Yul, the Honest Worm would eventually turn against him in order to gain the strength needed to withstand Oryx. Making a pact with Oryx's estranged son, Nokris, the two fled their families and sought a new world to rule.
At some point either before or after Nokris' excommunication, Xol created the Ogre Golgoroth to challenge Oryx, commanding the beast to devour the Taken King. However, his kin, Eir, intervened to remake the beast into an even more monstrous and powerful shape; serving Oryx instead and to protect the Tablets of Ruin.
After Nokris' excommunication by Oryx, Nokris and Xol departed from the rest of the Hive and set out to find a new world to rule. Nokris chose Mars in the Sol system, and arrived there with Xol and the Grasp of Nokris during the Collapse. Xol and Nokris engaged with the Warmind Rasputin and became trapped under the Hellas Basin of Mars, before being freed by multiple Warsat impacts in the region centuries later.
Upon reawakening, Xol and his worshippers, the Grasp of Nokris, sought to gain control of Mars by destroying the Warmind Rasputin. Their plans were interrupted by the intervention of the Guardian, who defeated Nokris and attempted to execute a plan by Commander Zavala to lure Xol into a trap with a Light-filled shard of the Traveler. Xol appeared before the Guardian and assaulted them telepathically, rendering them unconscious. The Guardian recovered shortly thereafter, however.
As Xol set about destroying Rasputin's neural network, he was pursued by the Guardian to the vicinity of Rasputin's central core, where he trapped the Guardian on a platform and engaged them in battle, using his jaws, bulk and paracausal abilities to attempt to destroy his foe. Ultimately, Xol was defeated by the Guardian using a super-charged Valkyrie javelin provided by Rasputin, leaving the Grasp of Nokris leaderless and reducing the remainder of the Worm God pantheon from four to three.
As with other Worm Gods, however, Xol's death was not his ending. Drawing power from the Sword Logic upon his defeat at the hands of the Guardian, Xol transcended physical death and communed with the Taken infesting the Jovian moon Io. When the Guardian proved themselves worthy of being a host to feed upon, he invoked the Anthem Anatheme and transformed into the Whisper of the Worm to keep drawing power from the Guardian's kills.
Xol is the final boss of the Will of the Thousands mission and of Warmind. He is encountered after he destroys the bridge to Rasputin's core. His primary attack consists of shooting fire blasts out of his mouth, which is also his critical spot, and if approached, he will rear his head back before lashing out viciously, instantly swallowing the player in one hit. Xol will take almost no damage until the Valkyrie is summoned by Ana Bray. Occasionally, Xol will retreat under the platform and will come up on a random side of the platform, charge, and will crush whatever is in his way. Along with that, he can cover the ground in Void energy that will briefly burn away at Guardians' shields before launching the player upwards. Hitting Xol in his weak spot with the Valkyrie will stun him for a short time. In addition, whenever he retreats, Xol summons Hive reinforcements. He summons more reinforcements as his health reaches zero, distracting the player from attacking and overwhelming them, and will also be immune as he retreats.
List of appearances