Cook has been a professional game designer since 1988, working primarily on role-playing games. Much of his early work was for Iron Crown Enterprises as an editor and writer for the Rolemaster and Champions (role-playing game) lines. During this period, he attracted fan and critical attention with the popular multi-genre setting Dark Space.
Eventually he took a job at TSR Hobbies, where he was a major contributor to the Planescape product line. Shortly thereafter, TSR encountered financial difficulties and was purchased by Wizards of the Coast. Under Wizards of the Coast, Cook worked as one of the three primary authors (along with Skip Williams and Jonathan Tweet) of the third edition of Dungeons & Dragons. Cook is the credited author of this edition's Dungeon Master's Guide.
Cook left Wizards of the Coast in 2001 and started Malhavoc Press to write material for the d20 System independently. Malhavoc's first product, The Book of Eldritch Might, is widely credited with demonstrating the viability of PDF publishing within the role-playing industry. Notable work under the Malhavoc banner includes Arcana Unearthed, a product he describes as a "variant Player's Handbook". He also wrote or co-wrote a few more products for Wizards of the Coast as a freelancer, including the d20 version of Call of Cthulhu.
Cook graduated from the 1999 Clarion West writer's workshop, and has published the novels The Glass Prison and Of Aged Angels. He has also published short stories like "Born in Secrets" (in the Amazing Stories), "The Rose Window" (in Realms of Mystery), and "A Narrowed Gaze" (in Realms of the Arcane). He also writes a continuing Call of Cthulhu fiction series, "The Shandler Chronicles," in Game Trade Magazine.
Malhavoc released Ptolus, a campaign setting based on Monte Cook's home game, in August of 2006. Ptolus was also the playtest campaign for the third edition designers. The book was unusually large and expensive for a roleplaying game supplement, being 672 pages and costing over $120 US.
Further material from Malhavoc Edit
Shortly after the release of Ptolus, which Cook has often described as the culmination of his original ambitions for Malhavoc, he announced that he would be focusing on writing fiction and other forms of creative work for the foreseeable future. White Wolf and Goodman Games announced his final RPG books. Monte Cook's World of Darkness, his own take on White Wolf's modern horror setting, was released at Gen Con 2007. From Goodman Games is Dungeon Crawl Classics: #50, "Vault of the Iron Overlord", which was also targeted for the same Gen Con release.*