Gaignun Kukai

Gaignun Kukai, whose real name is Nigredo is a supporting character in the Xenosaga series. He is the chairman of the Kukai Foundation.

History
Gaignun is one of the few remaining U.R.T.V.s. While he is officially the first son and heir to the industrialist Soze Kukai, this is a fake cover story. He was a designer child specifically designed along with the other U.R.T.V.s to be an anti-thesis to U-DO. Gaignun was U.R.T.V. number 669 and also a variant, meaning he was subjected to induced mutations during his embryonic development. Thanks to this, he has the power of telepathy and hypnotic suggestion, alongside a unique hair and eye color. Additionally, unlike other U.R.T.V.s, he does not react to U-DO's waveforms and merely repels them.

Gaignun spent his childhood at the Yuriev Institute, undergoing combat training against U-DO alongside his fellow U.R.T.V.s. As a child, he often spent his time hanging out with the other variants, Rubedo and Albedo. He was often the peacemaker and mediator of their group, comforting Albedo and reassuring Rubedo whenever he felt insecure about himself. However, he often felt left out due to their special connection as conjoined twins.

After Sakura Mizrahi was admitted to the Yuriev Institute for treatment, Gaignun, alongside Rubedo and Albedo, started going on periodic dives into her subconscious and befriended her.

At a certain point in time, he was approached by Citrine about the mission they had in common, taking down the Red Dragon if he were to ever go out of control. She also pointed out his peculiarity, his inability to destroy U-DO waveforms, which surprised him.

At an unknown amount of time before the Miltian Conflict, Gaignun rejected his mission as the U.R.T.V.s' acting executioner and shot his father Dmitri Yuriev. Unbeknownst to him, Yuriev went inside Gaignun's body and began resting until he could recover enough to take over Gaignun's body.

The U.R.T.V.s were sent in as part of the third descent operation by the Galaxy Federation in hopes that they'd be able to sever the link between the Zohar and U-TIC's weaponry during the Miltian Conflict and Gaignun was among them. He was partaking in the spiritual link that Rubedo had set up inside the Song of Nephilim, until he decided to sever the link out of fear of what their collision with U-DO's waves would do. As a result of this, many of the U.R.T.V. units, including Albedo, got infected by U-DO and started attacking civilians. Shortly after, Gaignun got separated from Rubedo due to an unknown cause and went looking for him, shooting down infected standard U.R.T.V.s to protect the civilians in the process. He returned to the Song, wounded and got attacked by a crazed Albedo. Gaignun hit Albedo with his waveforms as the failsafe of the U.R.T.V.s, which left him half-dead. Gaignun was also heavily wounded after their battle and was found by Rubedo who carried him until they were rescued by chaos and Canaan in the E.S. Asher. At this point, chaos refers to Gaignun as the rider of the black horse who carries famine.

At an unknown point in time, Gaignun and Jr. took care of a cat called Gaignun and chose to name themselves after it.

After their rescue, Gaignun and Rubedo were taken in by Helmer, who helped them establish the Kukai Foundation.

Episode I
Gaignun first appears in the game when the party heads to the Kukai Foundation. He comes to personally meet Shion and the others. Gaignun was in communication with Juli Mizrahi and tells MOMO that they'll ensure she gets to Second Miltia safely. Gaignun and Junior speak in private a little later and Gaignun believes Shion to not be as ordinary as Junior thinks. He provides Junior with a special gun as a present he won at a recent auction. Later, Gaignun speaks with Representative Helmer, with whom he has a long standing relationship. Gaignun tells him about their recovery of the Zohar Emulator and MOMO.

When the U-TIC Organization frames the Kukai Foundation for the destruction of the Woglinde, Gaignun is arrested along with the others. However the Federation Officer in charge, Lapis Roman, is an agent of Helmer's and arranges for Gaignun to be able to speak with him. He is eventually freed once Shion and the others are able to find evidence of their innocence within KOS-MOS' Encephalon. With the arrival of the Song of Nephilim and a large amount of gnosis, Gaignun and the Kukai Foundation have their hands full fighting off the gnosis while Junior and the others head to the Song of Nephilim, and after that Proto Merkabah. Gaignun's last scene in the game is a conversation with Helmer about U-TIC's target being on Miltia and him revealing to him that Albedo is still alive.

Episode II
Junior contacts Gaignun when they are chased through the streets of Second Miltia, but Gaignun finds himself a bit out of it, wondering what he was doing. He later meets with Helmer who asks him to do some reconnaissance. Gaignun and Albedo are able to communicate with each other through their mind. Albedo says Gaignun's true form is an executioner and taunts him over hanging around Junior while waiting to carry out his mission. Gaignun cuts the communication causing Albedo's arm to vanish, although he immediately regenerates it. Gaignun heads to the U.M.N. Control Center when they are about to investigate the Y-Data in MOMO.

It is later revealed that Dmitri Yuriev has the ability to restore his consciousness, using Gaignun as a vessel, which he does. Gaignun eventually regains control back over his body. He says for Junior to not trust his words.