Ya Zhen

Ya Zhen is an evil demon from the 2008 video game Jade Empire. He is a Toad Demon bound to Wild Flower's body to balance out the good demon Chai Ka the Heavenly Gate Guardian. He can appear as one of the player character's followers and possibly as an evil replacement to Chai Ka.

He's voiced by Gord Marriott.

Biography
When the deceased girl Wild Flower was resurrected to serve as the anchor of Chai Ka, Ya Zhen was bound to her as well as the balancing force to the Heavenly Gate Guardian. By using the girl, both demons are able to momentarily channel themselves to the mortal realm. They can also talk through her, with her eyes turning blue when Chai Ka speaks, or red when Ya Zhen speaks. Ya Zhen hates being bound to Wild Flower and often fights with Chai Ka over control. Wild Flower doesn't like at all the cruel Ya Zhen whom she refers to as "the Other", siding with Chai Ka who prevents the Toad Demon from harming her.

Ya Zhen appears only if the player talks with Wild Flower before the arrival to the Imperial City. By that time, she tells of the existence of "the Other" who harms her. When she's first spoken to in the Imperial City, Ya Zhen forcibly takes control from Chai Ka to speak with the player, revealing that the evil energies of the capital have strengthened him. He later makes an offer to the player: if they help him in taking all the control over Wild Flower's body from Chai Ka, Ya Zhen will serve them for the rest of the player's mortal life. At this point, Chai Ka and Ya Zhen serve as separate followers.

If the player hasn't decided between Chai Ka and Ya Zhen by the time the Imperial Palace is first entered, the more powerful evil energies present prompt Ya Zhen to attempt his ultimate takeover. The player must enter Wild Flower's mind and decide whether to help Chai Ka or Ya Zhen. If they side with Chai Ka, Ya Zhen is weakened to the point that he cannot extend his influence to the mortal realm or harm Wild Flower anymore. If Chai Ka's defeated, Ya Zhen assumes full control over Wild Flower's body and tortures her mind for her past resistance. He keeps his pledge and serves the player for the remainder of the game. If the Open Palm ending occurs, Ya Zhen serves the player for the rest of their mortal life, intending to move to other plans afterwards. If the Closed Fist ending occurs and the player becomes a god, Ya Zhen serves them proudly, patiently binding his time to move to greater plans.

Personality
Ya Zhen is a vile and selfish demon who makes no effort to hide his evil nature. Unlike his good counterpart Chai Ka, he cares nothing for their anchor Wild Flower or the heavenly orders. He desires freedom to do as he pleases and for that end, he's willing to offer his servitude to the player. As an immortal creature, he can be patient when he wants to be, saying that doing odd jobs for a few decades in the player's name would be worth his freedom. He appreciates acts of cruelty, expressing approval in the depraved acts of the player's enemies.