Doom (1993 video game)
Doom (typeset as DOOM in official documents and stylized as DooM in other media) is a 1993 first-person shooter (FPS) video game by id Software. It is considered one of the most significant and influential titles in video game history, for having helped to pioneer the now-ubiquitous first-person shooter. The original game was divided into three nine-level episodes and was distributed via shareware and mail order. The Ultimate Doom, an updated release of the original game featuring a fourth episode, was released in 1995 and sold at retail.
DRL (video game)
DRL (formerly DoomRL), short for Doom, the Roguelike, is a roguelike video game developed by ChaosForge based on the first-person shooters "Doom" and "Doom II". It's been in-development since 2002 and released for Microsoft Windows, Linux and OS X. Following a cease and desist notice from "Doom" trademark owner, ZeniMax Media, the game's name was changed to "DRL" in 2016.