In Destiny 2, the Vex mind that serves as the final boss of the Curse of Osiris expansion is Panoptes. Known as Panoptes, Infinite Mind, it controls the Infinite Forest, a vast Vex simulation located within Mercury. Its plan is to create a future in which the Light and Darkness disappear and all non-Vex life is erased.
The Guardian enters the Infinite Forest while searching for Osiris and his Ghost, Sagira. Panoptes initially overwhelms the Guardian and separates Sagira from the Ghost, forcing the Guardian to gather the information and allies needed for a return assault. During the final battle, Osiris helps hold Panoptes at bay while the Guardian damages and destroys the Vex mind.
Argos is a Vex boss from the Eater of Worlds raid lair, while Atheon is the final boss of the Vault of Glass. Quria is a distinct Vex mind connected primarily to the Taken and Savathûn, not the Curse of Osiris finale. Curse of Osiris launched in December 2017.