Gunman Chronicles is a futuristic first-person shooter computer game using the Half-Life game engine. It was originally planned as a total conversion for Quake; it then switched games to Quake II, followed by another switch to Half-Life, before being spotted by Valve Software and released as a stand-alone retail product in 2000.
Another review, done out of sheer nostalgia...
The environments, weapons and enemies were extremely varied and the story was enthralling enough to keep the game fresh all throughout; not to mention the weapon mode customization! Everything in this game clicked and the imagery was fantastic. Also, you could drive a damned tank. 'Nuff said.