The Urban Explorers returned from dusty archives with the first .PDF copies ever of the popular CityBook series from Flying Buffalo. This collection included all seven CityBooks and other supplements in Buffalo's popular Catalyst series of generic play aids for fantasy adventures. The CityBooks present dozens of individual shops, establishments, and characters, generically written to be compatible with any fantasy RPG and to fit smoothly in any urban fantasy setting. Originally published from 1982 to 1997, the CityBooks featured contributions by leading designers including Larry DiTillio, Liz Danforth, Michael A. Stackpole, Dave Arneson, Jennell Jaquays, Greg Gorden, and many more.

• CityBook I: Butcher, Baker, Candlestick Maker, CityBook II: Port o' Call, CityBook III: Deadly Nightside, CityBook IV: On the Road, CityBook V: Sideshow, CityBook VI: Up Town, and CityBook VII: King's River Bridge
• Treasure Vault, a collection of highly interesting items
• The first four volumes in the popular Grimtooth's series of devious dungeon dangers: Grimtooth's Traps, Grimtooth's Traps Too, Grimtooth's Traps Fore [no, there was no Three], and Grimtooth's Traps Ate
• Mercenaries, Spies, & Private Eyes and its solo Adventure of the Jade Jaguar

When we resurrected this Catalyst Bundle in August 2019, we added two titles that hadn't yet been scanned in 2017. The City of the Gods Map Pack is a Catalyst location sourcebook for a mystical realm where all the gods of Earth reside: Greek, Egyptian, Babylonian, Celtic, Asian, and many other pantheons. Mugshots No. 1 - The Case of the Pacific Clipper is a high-flying pulp-era solo adventure for Mercenaries, Spies, & Private Eyes written by Dungeons & Dragons co-designer Dave Arneson. All previous purchasers of this Catalyst Bundle's original July 2017 run also received the new additions automatically on their Wizard's Cabinet page. When you buy a Bundle of Holding early, you never worry about missing a title added later – even much later.