This topic might have a better name.
Weeping Angels (Hell Bent), as there are several Angels, including a baby.
Talk about it here.
A Weeping Angel came to Gallifrey to steal information from the Matrix during the Cloister Wars. It was trapped in the Cloisters by Fibre-optic cables and later used by the Matrix in an attempt to attack Clara, but she escaped. (TV: Hell Bent)