Gygax left TSR in 1986 over conflicts with its new majority owner, but he continued to create role-playing game titles independently, beginning with the multi-genre Dangerous Journeys in 1992.

[3]: 16  The family lived on Kenmore Avenue, close enough to Wrigley Field[6] that he could hear the roar of the crowds watching the Chicago Cubs play.

[14] By his teens, Gygax had a voracious appetite for pulp fiction authors such as Robert E. Howard, Jack Vance, Fritz Leiber, H. P. Lovecraft, and Edgar Rice Burroughs.

[4] Except for a few months he spent in Clinton, Wisconsin,[17] after his divorce, and his time in Hollywood while he was the head of TSR's entertainment division, Lake Geneva was his home for the rest of his life.

[10] Gygax cited as influences the fantasy and science fiction authors Robert E. Howard, L. Sprague de Camp, Jack Vance, Fletcher Pratt, Fritz Leiber, Poul Anderson, A. Merritt, and H. P.

Early that same year, Gygax published Chainmail, a miniatures wargame that simulated medieval-era tactical combat, which he had originally written with hobby-shop owner Jeff Perren.

Several aspects of the system governing magic in the game were inspired by fantasy author Jack Vance's The Dying Earth stories (notably that magic-users in the game forget the spells that they have learned immediately upon casting them and must re-study them in order to cast them again), and the system as a whole drew upon the work of authors such as Robert E. Howard, L. Sprague de Camp, Michael Moorcock, Roger Zelazny, Poul Anderson, Tolkien, Bram Stoker, and others.

[33][34] The two men each invested $1,000 in the venture—Kaye borrowed his share on his life insurance policy[14]—to print a thousand copies of the Dungeons & Dragons boxed set.

Worried that the other playtesters and wargamers now familiar with Gygax's rules would bring a similar product to the market first,[19]: 78  the two accepted an offer in December 1973 from gaming acquaintance Brian Blume to invest $2,000 in TSR to become an equal one-third partner.

[31] Gygax worked on rules for more miniatures and tabletop battle games including Classic Warfare (Ancient Period: 1500 BC to 500 AD) and Warriors of Mars.

[39] The Dragon debuted in June 1976, and Gygax said of its success years later: "When I decided that The Strategic Review was not the right vehicle, hired Tim Kask as a magazine editor for Tactical Studies Rules, and named the new publication he was to produce The Dragon, I thought we would eventually have a great periodical to serve gaming enthusiasts worldwide ... At no time did I ever contemplate so great a success or so long a lifespan.

[3]: 129 The Dungeons & Dragons Basic Set released in 1977 was an introductory version of the original D&D geared toward new players and edited by John Eric Holmes.

[41] In 1979, Michigan State University student James Dallas Egbert III allegedly disappeared into the school's steam tunnels while playing a live-action version of D&D.

[3]: 156  Mary Jo resented the amount of time that her husband spent "playing games"; she had begun to drink excessively, and the couple argued frequently.

[2] Gygax' life continued to unravel on the West Coast, as he rented an immense mansion, increased his cocaine use, and spent time with several young starlets.

[3]: 168 Gygax was occupied with getting a movie off the ground in Hollywood, so he had to leave TSR in the hands of Kevin and Brian Blume to oversee its day-to-day operations.

But almost at the same time, he received word that TSR had run into severe financial difficulties, and Kevin Blume was attempting to sell the company for six million dollars.

He charged that the financial crisis was due to Kevin Blume's mismanagement: excess inventory, overstaffing, too many company cars, and some questionable projects such as dredging up a 19th-century shipwreck.

[3]: 172  Gygax gained control and produced the new AD&D book Unearthed Arcana and the Greyhawk novel Saga of Old City, featuring a protagonist called Gord the Rogue; both sold well.

[28]: 237 Gygax brought in Don Turnbull from Games Workshop to manage the company, then worked with Mohan and Mentzer on a science fiction-themed RPG, Cyborg Commando, which was published in 1987.

In a literary declaration that his old world was dead, and wanting to make a clean break with all things Greyhawk, Gygax destroyed his version of Oerth in the final Gord the Rogue novel, Dance of Demons.

Gygax announced in 1988 in a company newsletter that he and Rob Kuntz, his co-Dungeon Master during the early days of the Greyhawk campaign, were working as a team again.

This time they would create a new multi-genre fantasy role-playing game called "Infinite Adventures", which would receive support through different gamebooks for each genre.

[28]: 239 After NIPI folded, Gygax decided to create an entirely new RPG called The Carpenter Project,[28]: 61  one considerably more complex and "rules heavy" than his original D&D system, which had encompassed a mere 150 pages.

[28]: 61–62  Work progressed favorably until March 1992, when TSR filed an injunction against Dangerous Dimensions, claiming that the name and initials were too similar to Dungeons & Dragons.

Gygax believed that the legal action was without merit and fueled by Lorraine Williams' personal enmity,[3]: 195  but NEC and JVC both withdrew from the project, killing the Mythus computer game.

Hekaforge was only able to publish the first two Lejendary Earth sourcebooks Gazetteer (2002) and Noble Kings and Great Lands (2003),[28]: 380  and the small company was having financial difficulties by 2003.

[28]: 381  Later that year, Troll Lord Games also published Castle Zagyg: Dark Chateau (2005), the adventure module written for the Yggsburgh setting by Rob Kuntz.

They became Jehovah's Witnesses, but he eventually left the religion; he remained a Christian, citing his favorite Bible verses of Matthew 5:15–16 a few months before he died.

[68] Immediately after Gygax's 2008 funeral, mourners adjourned to Lake Geneva's American Legion Hall to play games in the deceased's honor.