"You must be Potter's friend, Ronald Weasley. It's lich, L-I-C-H. Necromancers can kill and cannibalize their own for a power boost, which... ironically kills themselves in the process. Making them mentally insane with exacting focus, and nearly indestructible. She had Voldemort's remains, didn't she?" Bertrand said, his voice shaky. Severus nodded.