Quake and Unreal and Half-Life are all excellent games, but most of the time in these games you are expected to be bold and crazy. You hold a  shotgun, and run and dash, shoot everything that moves. But in THIEF, If  you act like you've always done in Quake or others, then, the game will be  over (i.e. you die) in a very short time. In THIEF you must walk slowly,  stop and wait, think the next step, retreat, sneak, hide, listen,  assassain,....This is really a great game! This is totally for connoisseur,  for those who had been tired of run and shoot blindly, for those like  tactics for those who can wait and are sly enough. In THIEF It takes much  more time to complete a level than other 1-person action games, but it  deserves. Never had a game make "wait" a fun and exciting thing,  and now THIEF succeed.