Hitman 2: Sniper Assassin

Hitman: Sniper Assassin is a great little detour around the mainline game, as it does well to still respect many of the principles that the main series is built upon. While it does limit Agent 47's ability to wander around the environment and wear different disguises to take out his targets, it still allows for creativity-kills and having multiple different paths to success, with a handy challenge mode that rewards point-bonuses to reach the upper echelons of the online leaderboards.