I remember this demo my dad downloaded roughly three trillion years ago (okay, around 2000, I think) where you were in some futuristic city filled with robots, or androids, or something like that. I remember it had graphics circa 2000, but the memory reminds me of FPSCreator graphics, so it may be made in that, as well. I think the title had something to do with the word "Lazarus", and may have been "Project Lazarus", or something like that.
Or, very likely, it could be something my shitty memory manufactured and I'm talking about a game that doesn't exist.
Also, a Christian game that has you attacking "heretics" with different coloured swords: gold, brown(ish), and I think silver. Now I know that game exists.