Blood (initially Horror 3D) is a first-person shooter game with a gothic horror theme and abundant dark humor developed by Monolith Productions (formerly QStudios) and was released in 1997 by GT Interactive (starting development under 3D Realms), published in Europe by Eidos Interactive. Similar to Shadow Warrior, it utilized an enhanced version of the Build engine featuring voxel graphics and room-over-room effects, as well as special material properties for surfaces.
Ports for the Sega Saturn and Sony PlayStation were once contemplated but never developed. Two expansion packs were released later that year: Blood: Cryptic Passage by Sunstorm Interactive, and Blood: Plasma Pak by Monolith. A sizable collection of fan add-ons and mods have been created, as well as a number of source ports and recreations, including the commercial Fresh Supply released in 2019 by Nightdive Studios using their KEX engine. A sequel was released a year after the original in 1998 called Blood II: The Chosen as the second game on Monolith's in-house LithTech engine.