Crota, Son of Oryx
Crota, Son of Oryx, also known as the "God-Knight", or “Light-Destroyer” and the "Eater of Hope", is an ancient and powerful Hive Prince who infamously wielded the Sword of Crota and killed countless Guardians during the City's ill-fated campaign to reclaim the Moon. Crota is the main antagonist in The Dark Below, in which the Hive seek to awaken him to lead their armies against humanity.
Crota is one of the many gods worshiped by the Hive. Though he is the "youngest" member of the pantheon, he is noted to be the heir to the Osmium Throne, the absolute sovereignty of the Hive. His purpose is to conquer Earth and destroy the Traveler on behalf of his father, Oryx, the ruler of the Hive. Crota has a sect devoted to him, who are spawned under his consort Omnigul, Will of Crota; though he himself belongs to the Blood of Oryx sect.
Long before the Hive stalked the Moon, Oryx raised Crota to be his champion the "Eater of Hope", traveling to many distant worlds and devouring them on his behalf and chasing after the Traveler. In time he gained reputation as a terrible demon. Once while he and his sisters were experimenting in the Ascendant realm, he accidentally let the Vex into his realm, as part of a trick by his aunt Savathûn. As he failed to eliminate them, the Vex created Quria, Blade Transform in order to deduce the Hive's Sword Logic and defeat the Hive while attempting to become gods themselves. The invasion forced Oryx's hand; as he dealt with the Vex, he threw Crota through the Vex warp gate as punishment, declaring "Come home glorious, or die forgotten!" As he went out conquering through time, he established many monuments and temples to his father, while feeding him tribute in the form of captured Light.
At some point Crota's spawn pursued the Traveler into the Sol System and conquered the Moon during the aftermath of the Collapse, hollowing it out into a war moon where they laid dormant until they launched an invasion of Earth during the early City Age. The Guardians barely repealed the Hive offense at the Battle of Burning Lake; not realizing the true threat the Hive posed, they launched a counterattack on the moon, which was later called the Great Disaster. The Sword-Logic proved to be too much for the Guardians, as countless heroes fell before Crota's Blades; in particular, the legendary Titan Wei Ning was slain personally by Crota himself, whom lead the Hive's hordes to victory during the battle.
However when an fight broke out between two Knights of Oryx and Xivu Arath (which ended in a stalemate), the former failed to make his tribute to a champion of the God-Knight. This setback costed Crota’s champion a significant tribute at the necessary time and lost a duel to a sergeant of the God of War. Having suffered a major loss of his temples and tributaries, Crota judged it best to sleep upon his throne world and recover his debts while his soul remain tethered to an Ascendant crystal, giving him a quick means of return to the real universe when need be. 
The Dark Below
Out of revenge, Eriana-3 led five other Guardians in an attempt to assassinate Crota at his throne world, but the hordes of Hive dwelling within the Hellmouth managed to overwhelm the fireteam, picking them off one by one. Only one of the Guardians, Eris Morn, survived, forever changed by her harrowing experiences trapped in the Hellmouth.
Crota's court also plays a major role when his consort Omnigul left the Hellmouth to gather the Hive in a full-scale invasion of the City. Having foreseen the imminent return of Crota, Eris Morn called upon the aid of a newly risen Guardian to aid her in dismantling Crota's army. The Guardian successfully assassinated Crota's closest lieutenants, including the Swarm Princes and their commander Sardon, leaving the Hive army in disarray and their general Omnigul killed in a Strike against her. To prevent Crota's summoning, Eris guided the Guardian to the Moon, where the chamber housing Crota's soul was located. The crystal tethering his soul in the Chamber of Night would be destroyed, banishing his shadowy presence from the physical world and thereby preventing his corporeal return.
Crota's end would be met by the Guardian leading a newly formed Raid team upon the Oversoul Throne, entered from the deepest pit of the Hellmouth. When conventional means failed before the Hope-Eater at his throne world, the Guardians turned Crota's own Sword-Logic against him with the Cleavers of his fallen Blades, permanently killing him.
Crota's demise ultimately caught the attention of his father, Oryx, the then God-King of the Hive and master of the Taken. Enraged by the death of his son, Oryx would bring his Dreadnaught into the Solar system and lead an army of Hive and Taken in revenge against the Guardians.
Ironically, Crota's lingering Ascendant power was necessary for the Guardians to access the rupture gateway into Oryx's sanctum. Returning to the Chamber of Night that tended to the crystal that house Crota's soul, the Guardians were able to gain a shard of the crystal but it did not hold of piece of his soul. The Guardians now had to disrupt Crota's death ceremony to gain a sliver of his soul. Entering Crota's Fortress, the Guardians narrowly slipped past the Hive defending his tomb and were able to fill the shard with Crota's death essence. With the Ascendant Shard, the Guardians were successfully able to enter Oryx's throne and defeat him. Like father, like son; Oryx would later fall to the Guardians who killed Crota in the King's Fall Raid.
Crota's disowned, heretical and forgotten brother, Nokris, would make his own stand against the Guardians after arising from slumber in the icy depths of Mars' Hellas Basin with his master, the Worm God Xol, Will of the Thousands. The herald of Xol sought to conquer the red planet for his god but like his former family, Nokris would fall against the Warrior of Light.
As Crota was the first Hive God the Guardians ever faced and one of their most notorious of foes, he haunts the Risen in their memories. Following the Scorn Hunts and the continuous fight for The Dreaming City, Crota's form would manifest as a Nightmare blocking The Guardian's path to the derelict Pyramid beneath the Scarlet Keep. The newly spawned Nightmare of Crota would prove too much for the Guardian to face, whom took an essence from it before they were saved by Eris Morn. The Guardian would later face the Crota Nightmare again as they were coaxed into the interior of the Pyramid, which they then succeeded in destroying.
Crota's immediate family would be survived by his daughters Besurith, Voshyr, Kinox, and the eldest Hashladûn. Atop the newly erected Scarlet Keep upon Luna in Sorrow's Harbor, the daughters laid plans for the Hive's future and to achieve vengeance against the Guardian for their ruined lineage using the Nightmares spawned by the Pyramid. Unfortunately for Hashladûn, the eldest daughter would lure the Guardian in a trap at the spire only to meet with the same fate as her father, and Besurith was killed defending a forbidden relic, the Cryptoglyph.
Crota is only mentioned in the base game and is never fought, but players are tasked with finding and destroying the Sword of Crota.
The players are tasked with destroying a crystal housing Crota's soul in The Wakening, before the Wakers of Crota can revive his corporeal form. It fires powerful blasts at the player and is protected by many Hive, including four Wakers of Crota.
Crota himself appears as the final boss of the Crota's End Raid. He will spawn after all players stand near his summoning crystal. Once he enters the arena, all Guardians will be inflicted with a debuff called Presence of Crota, which disables regeneration of both health and shield alike. To counteract this, one can pick up the Chalice of Light that spawns in the middle of the room; it can be picked up by anyone that needs to regenerate. Crota will not be vulnerable to attack at the moment, as he will be protected by a resistant shield. This gives Crota the opportunity to pelt Guardians with Darkness Blasts from afar, similar to Wizards. Meanwhile, a Swordbearer will show up at the bottom level. It must be killed in order to pick up its Ascendant Sword, which is the only way to actually damage Crota. In order to make him vulnerable to attack, all other players must focus all their available firepower on Crota's shield to disable it. The player carrying the sword must rush in quickly, as the shield can regenerate in less than a second. Nothing else will be able to damage him at this time. Once his shield goes back up, everyone else should be ready to shoot it down again so that the sword carrier can get in as much damage as possible. It will take multiple sword runs to bring Crota down. After Crota recovers, he will summon his Oversoul. If not shot down, it will instantly kill the entire team.
Age of Triumph added a Challenge Mode for Crota. To complete it, nobody can hold the sword more than once. Even if a player drops it, if they pick it up again, the challenge will fail.
List of appearances