A restoration field was added to the Pandorica so the Eleventh Doctor would be unable to escape by dying. It was used by the Doctor, once he escaped, to reanimate the nearly dead Amy Pond; to restore a near dead living being it needed a sample of the living being's DNA. In Amy's case, this came from her younger self. It later reanimated a Stone Dalek. The Doctor used it to revive himself when the Dalek shot him, nearly killing him. It is unknown where the Doctor got the DNA to heal himself, though since the Pandorica was already open, it is possible he did not need it.