Ken's Labyrinth | 1993 | Epic MegaGames | Ken Silverman (FPS)
I never really got into this game (to be fair I haven't played it all of the way through). It was coded by Ken Silverman who also designed the Build engine used in Duke Nukem 3D, Blood, Shadow Warrior, etc. In this game you can interact with characters, as well as play slot machines, and of course fight enemies. The full version was released as freeware in 1999.
Full Version (916k)
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