Mindjack
50 Achievements
1,000
20-25h
STAR
In Host Play, get hacked into by over 100 Hackers.
40
How to unlock the STAR achievement in Mindjack - Definitive Guide
If boosting with a friend have them join your game spawn then quit back out then rejoin, rinse and repeat till the achievement pops
If no booster is available pick a level from scene select and wait every now and then people will join from time to time (assuming the online isnt dead already)
What I did was play through the game with the game open so people can join and when it got full kick a few of them or one, so someone else will join or even the same person.
If after doing that and you've not unlocked it, you're best to just get to a spot in a level were no one who joins can progress any futher. And they'll just leave. You'll be surpriced how many people jump in and out over the night if you leave your game open like that.
To get this achievement you can do a few things. You can start a completely open host on a level and just stand there and allow people to join and quit until the achievement pops (and you can have a friend join your room by going to his friends list and joining your session in progress as long as he spawns over you and then quits and then rejoins again).You will get a lot of the 100 hacks out of the way if you do this the short way to get 50 wins for the "Red Devil" achievement for a friend.
This must be done in Scene Selection due to the fact that when you lose in campaign it does not count for the hack-ins by other players because they already hacked-in. When you lose in Scene Selection it requires all players to hack-in again and each hack-in will count.