007 Legends

This is 24 hours of actual playing. Time spent in lobbies/menus doesn't count. There is no shortcut. If you aren't interested in actually playing the game, you can idle boost this, but there are two slight problems:

1. You will need a certain number of people (I think four) in a lobby to automatically start up the game. There is no way around this. (You can press the start button to make the game begin - even with no other players present - but that would mean you couldn't be AFK for more than ten minutes at a time)
For those unfamiliar with the game, having so "many" people in a lobby isn't a given as the games online community is almost non-existant at this stage.

2. The game will kick you if you are inactive for about 2 minutes. This has a nice simple workaround: Rubberband your analogue sticks. You will be at the loadout selection screen cycling through them but the game wont kick you. Obviously a wired controller or a play and charge kit are required to stop the controller going to sleep. (I've also tried pulling the battery pack out and that seems to work although I can't guarantee its effectiveness.)

So in conclusion you can either play legit for 24 hours, play with a small number of people (or solo) but have to press start at the beginning of each match (turbo controllers might solve this) or idle with a large group (4 or more people) completely idle. The achievement will pop once the match finishes.