the Boxed Set. In the early '90s, TSR had a standard format for their boxed sets: two 96-page books, three or four big maps, and a pile of cardboard sheets. You can see this formula in Dark Sun, which includes a 96-page "Rules Book", a 96-page "Wanderer's Journal", two major maps, and a poster. However, Dark Sun also got to expand beyond those standards, probably as a result of the extra support that management was throwing its way. As a result, Dark Sun also included two unique spiral-bound "flip books" and a short booklet.

Beginning the Flip Book Adventures. Dark Sun was a box full of innovation, and the spiral-bound flip books were a large part of that.

The first spiral-bound book was the "Player Aid Cards". This was artwork to be shown to the players, an idea that TSR had originated way back in S1: "Tomb of Horrors" (1978), but which was pretty uncommon by the 2e era.

The second spiral-bound book was the "Dungeon Master's Book", which included the actual adventure. However, it was a non-traditional adventure for the time period: it was split into individual encounters that included specific sections for "Setup", "Roleplaying", "Statistics", and other important elements. Each encounter also ended with a list of which encounters the GM should "flip" to next, based on what the players did. The result was the sort of event-driven adventure that was common in 2e days, but with very different, easy-to-use formatting and with more room for player choice.

The flip-books were complemented by a "Story Book" that contained a short story, "A Little Knowledge", which introduced the adventure.

This innovative format would be used throughout the Dark Sun adventures, beginning with DS1: "Freedom".

Expanding AD&D. Dark Sun also dramatically innovated the AD&D game, taking it in new directions that had been unseen in the decades before.

• Characters were more powerful, with stats rolled on 5d4, beginning with more funds, and starting at third level.
• The classic but "twisted" races were complemented by totally new races: the half-giants, the muls, and the insectoid thri-kreen.
• Many traditional classes were also transformed. Because there were no gods, clerics were powered by the elements. Wizards could be preservers who protected Athas' ruined environment or defilers who made it worse. Psionicists were also used as a standard class for the first time in any setting.
• Even more varied classes such as the gladiators and templars also appeared.
• Experience points were expanded with new rules for individual class awards that gave out points for acting in-character for a class.

Gaming Tropes. One rules change deserves an additional comment: the "character tree". Over the years, D&D had become focused on the idea of each player playing just one character, but by the '90s other games such as Ars Magica (1987, 1989) were challenging that idea. Dark Sun was the only latter-day D&D game to ever embrace this change; it did so through "character trees" where each player had four different characters and could decide who to play in each individual game.

Writing Tropes. Finally, Dark Sun also innovated the role of fiction in a game world. Not only did it include fiction for players to read, but it also included first-person narratives in the rule books themselves.

Expanding Athas. Dark Sun was of course the introduction to the world of Athas. Unlike the traditional settings of the Forgotten Realms, Greyhawk, and Mystara, Dark Sun detailed just a small part of the world of Athas called the Tyr Region. Future books would continue to extensively detail this relatively small area of Athas over the course of the original Dark Sun run (1991-1995).

In order to introduce Athas, Dark Sun offered a big overview of the society of the Tyr Region, as well as short notes on many of the major cities and other areas in the region.