Although the gameplay is extremely simple, Telengard is by no means easy. You'll die a lot before gaining a level, and new, better weapons are hard to come by. There is only one character class to play as-- a warrior/wizard combination, although you can re-roll the starting stats and cast spells during the game. Telengard features some neat ideas that became commonplace in Roguelikes, such as scrolls, and teleporters you can use to warp around the dungeon. All in all, a respectable dungeon hack that didn't set any standards, but probably inspired a lot of authors to program Roguelikes of their own.

Note: Apparently this Avalon Hill version is one of the few commercial versions of DND, also by Daniel Lawrence, which may well be the very first computer RPG ever created. Read more info and download other DND versions at the Unofficial DND Site below! [thanks to ZDim for the link]