|Affiliation|| Muzen (former)|
Lords of Darkness
|First Appearance||Tenchu: Wrath of Heaven|
They are part of an organisation known as Muzen who delivers justice when the law fails to do so, for a price. They are at odds with Tesshu and are also in league with the evil sorcerer Tenrai, working against the Azuma ninja. They are the main antagonists in Tesshu's campaign, while Ukyo is a minor antagonist in Ayame's campaign.
When killing, Ukyo lures the victim in to a deadly trap, where Sakyo will then appear and cut down the victim, when it is too late to realize there are two of them.
In Rikimaru's campaign, he sends his men to monitor the Azuma ninja and hinder his progress.
In Ayame's campaign, Ukyo battles Ayame at the abandoned temple while she was searching for one of the three jewels. During the battle, Sakyo prepared to strike Ayame from behind but was stopped by Tatsumaru who later informed him at Tenrai's fortress that he would be the one to kill her.
As the main antagonists in Tesshu's campaign, the Jinnai brothers play a more significant role. Ukyo ambushes Tesshu at a waterfall at the Buddha temple while he was awaiting payment for killing Ganda. He is imprisoned at the Limestone Cavern, but Tesshu uses one of his needles to escape from his locked cell after Jinnai threatened him to kill his own boss before leaving. After his escape, the Jinnai brothers arrived at the cemetery ahead of Tesshu and slew his informant. This is when Tesshu, watching from his hiding place, discovers that there are two of them. Later at the Ronin Village, Tesshu reports back to his boss Zennosuke. Zennosuke gives Tesshu the assignment of silencing Jinnai. As Tesshu left, Zennosuke bends forward to reveal a sword stuck in his back. This suggests that Tesshu shared a close relationship with his boss, as Zennosuke could have not revealed his fatal injury to Tesshu so as not to worry him (in Ayame's story, Tesshu had mistakened Ayame to be Zennosuke's killer and announced that he would avenge his boss before attacking). Tesshu meets Ukyo in the Ronin Village, and they duel, with Tesshu emerging as the victor. Tesshu then reveals Sakyo, and the two share a short conversation a protagonist typically shares with his mortal enemy. Sakyo seems unmoved by the death of his brother, instead abandoning his disguise before announcing that it was time for the world to fear the name Jinnai Sakyo. The two battle, with Tesshu winning the fight again. Before his death Sakyo reveals that he had rigged the village with explosives that may detonate at any moment, but Tesshu seems to pay little heed to this ominous statement and silences Sakyo. Tesshu is then wounded by a Ronin in an ambush. Tesshu kills his attackers to 'send some friends to join Sakyo' and dramatically leaves the village as it explodes.
He is a skilled swordsman and fast at pace, making him a formidable opponent for Tesshu. He is also fought in Ayame's story, in Return from Darkness.
- He appears in all three campaign, In Rikimaru's story, he is seen briefly where he sends his men to kill Rikimaru, in Ayame's story, only in Return from Darkness, he fight Ayame, but was stopped by Tatsumaru, in Tesshu's story, he is the main antagonist, and is the final boss.