Phantom Piper

The Phantom Piper was the McCrimmon clan's equivalent of the Grim Reaper. It was said to be a McCrimmon himself and appeared right before a McCrimmon died. When on the Moonbase in 2070, Jamie mistook a Cyberman for the Phantom Piper. (TV: The Moonbase)

The Phantom Piper was also known as the "King of the Dreamspace", and existed in the dreams of soldiers in every war, including Troy, Culloden, and the Somme. He said he was "the only one listenin'" when soldiers cried out at night. He got a physical body outside of the Dreamspace when he tricked the Twelfth Doctor into bringing the TARDIS, which had a code carved into it, to Alan Turing on the Moon, who used Block Transfer Computation to translate the code and, unwittingly, made the Piper, who was a part of the code, manifest. (COMIC: The Phantom Piper)