What is Quria? Quria, Blade Transform was a mind built by the Vex to understand and utilize the Sword logic, when the Vex entered Oryx's ascendent realm, thanks to Crota and Savathûn. He realized that if he killed everything, he would become strong. So he slew a lot of Oryx's forces, and became a major force in Oryx's realm. Eventually, however, Oryx cornered Quria. As a last-ditch effort, he tried to simulate Oryx, but he couldn't understand the Darkness within him, or the worm. So he made an Aurash. Finally, after having a little conversation with her, Oryx took Quria. The taken Quria is then gifted to Savathûn, his sister, known for being cunning. Oryx says that Quria has a bit of will left, so it can surprise her.

Correct. But now make a theory on what savuthun could have done with Quria. And I didn't want you to flat out give me the info, but give tid bits of it through a theory

Savathûn could have been planning to attempt to use Quria to attack Oryx. When Oryx gifted Savathûn Quria, he may have made a terrible mistake. Quria, being a mind of the Vex, is able to summon them and give them orders. But now, Quria is placed under Savathûn's control, giving her basically two armies. She also asks Oryx if it will "let the machines into my throne..." in verse 44 of the Books of Sorrow, meaning she knows what Quria is capable of. By using her own brood, and the might of the Vex army, which kept the Deathsingers [u][b]and[/b][/u] Crota occupied for a long time. Combined with her forces, the Vex and Hive could topple Oryx and his forces. And then Savathûn will kill him, as this is the Hive way.