Shadow Warrior

Shadow Warrior is a first-person shooter video game developed by 3D Realms and released on May 13, 1997 by GT Interactive. Shadow Warrior was developed using Ken Silverman's Build engine and improved on 3D Realms' previous Build engine game, Duke Nukem 3D. Mark Adams ported Shadow Warrior to Mac OS in August 1997.[1]
The game's improvements included introduction of true room-over-room situations, the use of voxels instead of sprites for weapons and usable inventory items, transparent water, climbable ladders, and assorted vehicles to drive (some armed with weapons). Although ultra-violent, the game emphasized tongue-in-cheek humor and contained some sexual themes (although less blatantly than in Duke Nukem 3D). A combination of Duke Nukem 3D and Shadow Warrior was published by GT Interactive in March 1998, titled East Meets West.[2]
On April 1, 2005 3D Realms released the source code for the Shadow Warrior engine under the GPL, which resulted in the first source port a day later on April 2, 2005.[3]
On May 29, 2013 Devolver Digital announced the game would be free to obtain for a limited time on Steam,[4] after a promotion to offer redemption keys for it on Facebook was exploited.[5] Later that day they announced that they decided to offer copies of the game on Steam for free forever.[6]
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