Doctor Who: EVERY NuWho Villain And Monster Ranked Worst To Best
218. Cyberium
Appears in: The Haunting of Villa Diodati, The Timeless Children.
A combination of a life form and a weapon, the Cyberium is a quicksilver artificial intelligence that controlled data, strategy, and decision-making for the Cybermen (naturally) during the Cyber Wars. It also contains the knowledge and future history of all Cybermen. Talk about spoilers.