Linley’s Dungeon Crawl:
Linley’s Dungeon Crawl was started back in 1995 by Linley Henzell. Henzell left four years later when Linley needed to shift focus to his law degree and stopped developing Crawl. However this was not the end. He released the code under the GPL so anyone could work on it and work on it they did. When Linley left the game was up to version 3.30 and now it’s up to 4.0.0 (beta 26) with a few variants floating around the web. Most notably Dungeon Crawl Stone Soup, but we’ll talk about that one in a minute. Unfortunately progress on Crawl has seemed to have halted with 4.0.0. The homepage hasn’t posted any news on it since 2004.
Enough history now for the good part. Crawl is a single dungeon roguelike with the main quest being to delve into the depths of the dungeon to retrieve the Orb of Zot and return to the surface. You’ll of course face an assortment of creatures whose only goal is to stop you on this quest.
From most accounts Crawl is a semi-lite roguelike. Easier to understand and jump right into than others like ADOM.