Nero is one of Ayden's Pokémon currently residing at Ayden's home in Phenac City. He is also the mate of Nina.
With a territorial nature, Nero is always one to love a fight. He prefers close confrontations to display his power and impress his mate Nina. Many of his moves are physical and he has immense strength.
Ayden encountered Nero alongside his mate, Nina in Route 3 of the Kanto region. The two had been members of opposing herd of their species. Fearing that their love would threaten to destroy the foundation of their herds, Nina and Nero fled to live a life together. When they met Ayden, she challenged them to a double battle and while she caught Nina first, Nero took a little while longer, being far more resilient.
He was primarily used by Ayden during her time in Kanto and now currently resides in her home in Phenac City.