T1-4: Temple of Elemental Evil

The Temple of Elemental Evil is one of the most famous Dungeons & Dragons adventure modules in the world, after the Tomb of Horrors. Gary Gygax's opening movement, Village of Hommlet, came out as a standalone in 1979, which sold well itself; but due to Circumstances the other modules didn't follow. After several years of TSR teasing Frank Mentzer fixed it all up and published the whole thing (including Hommlet) as a single book with a map booklet, in 1985. That's the one that justified the hype.

It's an epic dungeon delve that revolves around the players breaking into the combined dungeon-temple of the Cults of the Princes of Elemental Evil - the four Archomentals Ogremoch, Imix, Olhydra and Yan-C-Bin. The Temple turns out to be the prison for demoness Zuggtmoy, whose cult has been manipulating the others'.

ToEE has since received multiple different iterations across different editions. Monte Cook did a sequel, Return to the Temple of Elemental Evil. This brings in Tharizdun as well. Most of that takes place in the Temple of All-Consumption; a stripped-down Temple of Elemental Evil serves as the endgame here.

A 3rd Edition Dungeons and Dragons based video game version was released in 2003. It is best known for having the most accurate adaptation of 3E rules to a video game and being an excellent example of turn based combat, and as being a schoolboy's lesson for decent quality-control due to its massive game-breaking BUGS. Tim Cain actually owns the rights to the source code for it and Arcanum and wants to release it (and fix the bugs), but his contract won't let him because it would allow for bypassing the CD check DRM that was broken the week it came out and sold without since 2010.