R: That's a bit complicated, haha.
I played two characters both suffering from dissociative personality disorder: Kiriga / Ki'yumé and Vao / Ki'gan. I'll talk about them more in details. For those who are not interested, you can skip to the next question!
Kiriga was a young Zoraï in search of meaning who was seduced by the apocryphal Kamic precepts preached by the Atys Prowlers. In short, the Atys Prowlers revered the Kamis and Ma-Duk, but refuted the writings of Hoi-Cho about the Kamism of Revelations. They followed their own writings: the Black Cult of Ma-Duk. Like all members of his guild, Kiriga was a religious fanatic who waged a permanent war against the Karavan and its supporters, and was also very critical of other Kamists whom he considered too limp.
The years passed, and gradually the Atys Prowlers guild fell apart. Mad with anger and sadness at seeing his comrades desert one by one, some even joining the ranks of the Karavan, Kiriga fell into a deep depression. He began to consume toxic psychotropic drugs and learned to create them himself.
This is how he created the Black Sap (or rather the different types of Black Sap), of which he was the first guinea pig. Little by little, the drug destroyed him and gave birth to a monstrous personality: Ki'yumé. A horrible being whose only ambition was to create a maximum of chaos.
To reach his delirious objectives, Ki'yumé answered the call for the Marauders launched by Akilia. An Akilia who had, according to him, sunk in a murderous madness for already a long time. Accompanied by comrades to whom he offered his stimulating psychotropic drugs, he co-founded the Marauder Clan of the Black Sap.
Over the next few years, Ki'yumé wreaked havoc on the New Lands, carrying out several attacks and capturing the Awakened Ki'atal. He finally died under mysterious circumstances during the Second Great Swarm, as did many other homins.
Vao Lu-Hoo, also a Zoraï, was one of the emissaries of the Clan of the Black Sap, who was captured by the Zoraï Theocracy while on a diplomatic mission to Zora. What the Theocracy did not know at the time was that Vao was also one of Ki'yumé's disciples. A disciple who had been chosen not without reason. Indeed, Vao was suffering from dissociative identity disorder caused by severe childhood trauma. For Ki'yumé, he was a perfect testing ground.
Locked in Zora's jails during the Second Great Swarm, Vao survived the Kitins' attack and fled when the attack subsided. Unable to face the mountain of challenges ahead, he gradually let his second personality take over. This one was called Ki'gan and never gave back control to Vao. For several years, Ki'gan searched for his master, in vain, but found nevertheless some of his fellow Marauders. As the last of them to know the secrets of Ki'yumé's drug production, he finally replaced him as the Clan's alchemist.
During the long years that followed, Ki'gan, like his late mentor, carried out numerous attacks against the various Atysian nations. However, unlike Ki'yumé who seemed to be driven only by madness, Ki'gan was a true political activist, wishing for the abolition of governments and the rebellion of homins against the Powers.
One day, and without anyone knowing why, Ki'gan disappeared. When he reappeared a few decades later, it was not Ki'gan who showed up, but Vao. An amnesic Vao, unaware of his criminal past and from whom 30 years of life had been stolen.