Catacomb 3-D (also known as Catacomb 3-D: A New Dimension, Catacomb 3-D: The Descent and Catacombs 3) is the third in the Catacomb series of video games (created by the founders of id Software), and the first of these games to feature 3D computer graphics. The game was originally published by Softdisk under the Gamer's Edge label, and is a first-person shooter with a dark fantasy setting. The player takes control of the high wizard Pelton Everhail in his quest to defeat the evil Gremlinar, also known as Nemesis.
Catacomb 3-D is a landmark title in terms of first-person graphics. The game was released in November 1991 and is arguably the first example of the modern, character-based first-person shooter genre, or at least it was a direct ancestor to the games that popularized the genre. It was released for the MS-DOS with EGA graphics. The game introduced the concept of showing the player's hand in the three-dimensional viewport, and an enhanced version of its technology was later used for the more successful and well-known Wolfenstein 3D. The game's more primitive technological predecessor was Hovertank 3D.
Source: Wikipedia, "Catacomb 3-D", available under the CC-BY-SA License.
You are Petton Everhail, High wizard of Thoria, the most powerful living wizard in the world and you've got a problem. The evil lich Grelminar, undead for over 200 years, has imprisoned Nemesis of Kelquest. (Nemesis is troublesome, but he's the only accessible person that can walk the Wildways, the super-natural paths to other dimensions.) Even you, an archmage, cannot travel to the places that Nemesis can. And so you journey to retrieve his body, now frozen in magical amber but still alive, from Grelminar's Keep on the dark island off the coast of Garacy. You had best be careful, or you'll be Grelminar's next prize. . .