Formally known as Cyrus Gold, Solomon Grundy came into existence after Gold's brutal murder and ruthless experimentation at the hands of Ra's al Ghul and the League of Assassins as part of their plans to discover the secrets of immortality. After he died dozens of times from the inhumane torture only to be brought back to life for more, Grundy was left broken in body, mind, and spirit. Grundy grew to relish in his own pain and suffering and inflicted the same on anyone else who was unfortunate enough to wander across his path. After he brought under the control of The Penguin for many years, Grundy was used as a weapon to wipe out anyone who stood against Cobblepot's criminal empire.