Much like Silveress, Nychus' past is a complete mystery, except that Nychus was supposedly one of the strongest warriors of the Snow Leopard Clan. Years ago, prior to Silveress' sudden death, Nychus was placed under the care of her daughter, Lilya, under a promise that he would protect and raise her for the future of their dying clan. However, it was soon revealed that Nychus' intentions were not as Silveress had predicted, as he would train the child in the art of assassination until years later when the two eventually became partners and top Assassins of the world. In 1916, Nychus and Lilya were hired by Rasputin, who was plotting to overthrow the Nicholas the Tsar and his family. Together, they nearly wiped out the entire Romanov line, all except for Anastasia and Marie, both of whom tried to escape. But when they caught Anastasia, Nychus ordered Lilya to kill the girl while they had her, but initially she refused to harm a child. When Nychus attempted to finish the job himself, Lilya ultimately betrayed him, scarring his face with his own poison, and drowned in the frozen lake along with Rasputin, stuck in a state of limbo ever since.
Years later, Nychus and Rasputin made themselves at home in the Nether Realm. Nychus, now permanently bound to Rasputin's power, had since covered his entire face in bandages and preparing for the day of his escape when he would get his revenge on his former partner. Upon learning that Anastasia was still alive, now under the name 'Anya', travelling with two con artists, the Fantasy Adventure Team, the Trimaxian Adventure Crew, and his former partner Lilya, now under the name "Linde" (Having consumed an Amnesia potion out of guilt). Determined to finish where they left off, Rasputin and Nychus made two attempts to kill the group en route to Paris, both failing miserably.
On one such attempt, while the group sailed from Germany to France, Nychus was sent to the ship as a messenger to warn his former partner that they would kill her and her friends once they disposed of the Grand Duchess herself. Overcome with desire for revenge, Nychus attempted to kill his frightened partner until his plan was ultimately foiled by the spirit of his former leader, Silveress, who had his soul sent back to the Nether Realm and thus keeping Linde safe.
Finally, after betraying two former Council of Shadow members by absorbing their souls, Nychus and Rasputin had the power to finally reach the surface to kill Anastasia and Linde once and for all. They captured Linde on a bridge, after she regained her memories the other night, and intended to make her watch as they lured Anastasia, who also recovered her memories, into a trap and ensure that she was "missing" forever. But when the two adventure teams interfered to aid the girls, Nychus' disfigured face was revealed (The poison having eaten three-fourths of his face, in addition to paralyzing his right-half) and a huge battle ensued between good and evil.
During the battle, Nychus easily took down the Fantasy Adventure Crew, one-by-one, until he finally stood face-to-face with Linde, who finally stood up against her former master and determined to confront what she always feared. Temporarily impressed with Linde's sudden bravery, the two Assassins fought to a near stalemate until Nychus eventually overpowered his apprentice with his heavily experienced kung fu skills and training. Just as he was about to finally get his revenge, Isaac the Media Hunter, member of the Trimaxian Adventure Crew, sliced off Nychus' arm and ultimately beheaded the Snow Leopard.
It is then assumed that he died prior to Isaac's interference or after Rasputin's reliquary was destroyed by Anastasia.
- Nychus became the Fantasy Adventure Team's enemy in Benny, Leo, Johnny, and Rae Meet Anastasia.
- It has been hinted in the story that Nychus worships a legendary Snow Leopard, Tai Lung, the antagonist from the movie Kung Fu Panda.