Xivu Arath and her craving for war have brought her to the Tangled Shore in efforts to breed a new dark army and seize the power vacuum left in the wake of Oryx's death and Savathun's hiding. Xivu Arath is the puppeteer pulling the strings behind the events of Destiny 2 Beyond Light's Season of the Hunt, using totems known as cryptoliths to raise a dark army of more than just Hive, but of Eliksni and Cabal as well. Her High Celebrant is watching over the operations and killing anyone who dares to interfere, including Osiris's ghost Sagira, who sacrificed herself to save Osiris in the wake of being killed by the High Celebrant.
The Tangled's Shore's resident crimelord Spider has asked guardians for their help in removing Xivu Arath's presence from the shore -- Xivu Arath is corrupting his Eliksni and turning his forces away from him. The guardians have agreed to help Spider and Crow rid the shore of Xivu Arath's cryptoliths in exchange for all the loot we can carry back to the tower, but they're also going to enact a little revenge in the name of Sagira and Osiris. But to truly understand Xivu Arath's goals, we have to go back to the very beginning -- before the Hive ever existed.
Xivu Arath is a Hive god of war, an aspect of the essence of war, but she was not born this way; she took her power from the darkness itself. She communed with the Ahamkara dragons, also known as worms, hidden deep beneath the surface. These worms were a direct connection to the darkness and could grant wishes of infinite power. Xi Ro wished to be a great knight and conquer her enemies, and thus the worm gods granted her the knight morph of Xivu Arath. Her sisters were also granted wishes and took the king morph of Auryx (Oryx) and the mother morph of Savathun. These three Hive gods and their followers were known as the Osmium Court until they created the Hive.
From there, Xivu Arath would lead the newly created Hive armies and conquer civilization for eons to come. The Hive conquered hundreds of planets and left genocide in their wake, becoming the very definition of the Sword Logic -- the genocidal creed the governs the Hive's existence. At one point, she sacrificed herself to her brother Oryx to endow him with more strength. He would take this strength and use it to become the Taken King. As the Taken King, he waged war for thousands of years and Xivu Arath was reborn out of the thousand-year war against the Ecumene. "I am war, and you have conjured me back with war," she said upon her revival. Xivu Arath's very nature is defined by conquest and death. She breeds her dark armies to devour all life in the name of the Sword Logic.
The legendary warlock Osiris knows first hand how dangerous Xivu Arath is, and experienced guardians remember how deadly Oryx, the Taken King, was. With Savathun lurking and laying the final dominos for her plan, it's almost certain Xivu Arath will act swiftly and prove her worth in her siblings absence. Xivu Arath learned the art of war and death by killing and being killed by her siblings over and over for thousands of years. They practiced death so they could become it. Hive Gods cannot technically die in this plane of existence. They can only truly be killed in their home dimension, known as a Throne World. These are the dark plains of existence guardians travel to in the Dreaming City and throughout the King's Fall and Last Wish raids.
It's only a matter of time before guardians face down Xivu Arath, perhaps in her own Throne World. If not this season, maybe in an upcoming season in some precursor to '21s expansion The Witch Queen. Maybe we will be caught in the middle of a Hive civil war between Xivu Arath and Savathun. Or could the Osmium siblings align their forces against us? Guardians should pray to the traveler that they face down Xivu Arath later rather than sooner. Xivu Arath knows only one love in this existence, and that love is war.