There's a number of gimmicks in the Hitman series that I enjoy (and conversely some that I don't enjoy). In Hitman 2, there's the mission where you don't have positive ID on the target and have to get some help from the handler to proceed. In Hitman 3, a certain mission works on a timetable (guy has a nuke and his ship gets stormed by SWAT), and you can skip the timetable ahead through your actions (e.g. if you get the SWAT member disguise the assault triggers faster; this way you don't have to tediously wait after acquiring the disguise). You can blend in with the SWATs during the assault, you can steal the SWAT sniper rifle, you can disguise as a terrorist, wait for the assault, kill the target and steal the remote for the bomb (as if threatening to detonate it), then walk to the helicopter he demanded, etc. There's the famous one in Hitman 4 where shooting your target while he's on the stage doesn't count as a ballistic kill but an accident as long as you time it with the execution scene, and you can even dress up as an actor to do it.