Deadlands: The Way of the Brave
Angel of Mercy
Clockwork cherub intended to help man but became a murderous machine instead
The Angel of Mercy was an invention by Dr. Ezra Whitehall. It was designed to perform as a medical assistant during surgeries. It was being transported to Salt Lake City when it was inhabited by gremlins. The gremlins used the angel to kill several people on the train until the clockwork cherub was destroyed by the posse.