The fourth edition came in a red and black double-pack, and featured 520 cards taken from every expansion and mainline set, augmented by over 200 new designs. Some cards that were not updated for the 3rd edition were changed with this release. The red box in this twin-deck pack included a 55-card deck playable directly from the packet, while the black box included a set of revised rules and a booster pack of 12 cards from the "Dragonomicon" expansion. By the time the fourth edition starter pack made its debut, the future of TSR was uncertain, leading to production problems. Three more booster series, "Draconomicon", "Nightstalkers", and "Dungeons", were released. Though they all sold out immediately, these sets were produced in small quantities. Shortly thereafter, Wizards of the Coast bought out TSR.