Layla Hassan is the Animus user who relives Eivor's memories in Assassin's Creed Valhalla. In the modern-day sections, Layla investigates the Viking-era genetic memories recorded in Eivor's DNA.
Valhalla was released in 2020 and follows Eivor, a Viking who leaves Norway and helps establish a settlement in ninth-century England. The historical narrative connects Eivor with the Hidden Ones and the Order of the Ancients.
Layla's Valhalla storyline continues directly from her role in Origins and Odyssey. She enters a cave in Norway while investigating a global magnetic disturbance, leading to major developments in the modern-day plot.
Desmond Miles is the Animus user in the earlier trilogy, while Basim is primarily a historical character and later a playable protagonist in Assassin's Creed Mirage. William Miles is Desmond's father and a senior Assassin, not Valhalla's main Animus user.