HacX: Twitch 'n Kill

Hacx was originally released - as an add-on for Doom II - by Banjo Software as a commercial release in the late 90's. It later become a free downloadable product. Since Banjo was trying to rush the game out to the market prior to the release of Quake, it was released as a faulty and rather ill-refined game - some of the maps are rather amateurish and incomplete, a whole lot of texture bugs, etc. Banjo and crew were able to fix many of the texture bugs and released version 1.1, which had its own set of problems. Despite the problems of the original releases, Hacx remains quite popular within the Doom community today - over 10 years later.