Diamond was, according to legend, Sir Isaac Newton's favourite dog, who, by upsetting a candle, set fire to manuscripts containing his notes on experiments conducted over the course of twenty years.

DD's exact breed is unknown, being described as either a wolf or a dog in various sources, and in some cases, even a wolf dog hybrid. Although the Rhodesian Ridgeback concept was dropped, it did appear in the in-game data, and could be "recreated".