Byaku Shin is the true main antagonist and final boss of Project X Zone 2. She is said to be part of Ouma's 101 Wombs Project, as mentioned in Super Robot Wars OG Saga: Endless Frontier EXCEED, and she is the result of that project. Her name translates into the 100 Gods, and her goal is to unify the worlds through Shibuya and rule over it as a god.

Project X Zone 2

She is fought similar to Meden Traore from the first game, but the only difference is that you have to defeat Sigma, Pyron, Ranmaru, Kamuz, and Metal Face, followed by Dokumezu, Dokugozu, Sheath, then Saya before attacking Byaku Shin, and you must also fight off waves of enemies from reaching the three pillars or you automatically lose.

Crosspedia Entry

Originally developed as Kyuju Kyu's upper body prototype by Ouma's Far East Headquarters, it has gone haywire as a result of losing its living core control device and has since followed its own evolutionary path.

It can command many different types of monsters and generates a form of energy capable of smashing through dimensional walls. In combat, it primarily uses the energy stored in its chest for projectiles and the high-powered beam sabers on both of its arms for melee. Its arms can also be fired as projectiles in their own right and controlled remotely.

Incidentally, the golden chains that appeared in each world were originally released from Byaku Shin's body, as a kind of beacon used to pinpoint each of Kyuju Kyu's parts that had been scattered across dimensions.