There is an easy way to cheese this achievement with one other player. Follow the below steps:
-Ensure both players are level 5+, you have a stalker dossier, and both players have enabled stalkers by visiting the van (if you do not have the disable stalker option in the gameplay options menu, you haven’t enabled it).
-Have a friend host a friends-only game and join to make it coop (host will not be Stalker).
-Have BOTH players start with the crossbow
-Press Select after the game loads, press RB to highlight backpack, then have the non-host person that wants to be the Stalker highlight their dart and drop it for the other player.
-Have the player that dropped their dart quit the game and rejoin. Continue dropping and rejoining until the host has a full inventory of darts and a few extra dropped on the ground in any easy to find location.
-Since spotting incapacitated enemies will net you about 100 Stalker points, you need enough darts to hit 5 enemies and have extra for backups since sometimes they don’t count 100 (especially if you record them back to back too quickly)
-Once the host player has enough darts, have the non-host player quit and immediately stalk a game. It may be good to check the lobbies to ensure there aren’t too many stalkable games and do this at low volume periods, but we have done this every time with no issues with connecting to the friend game as it registers it coop after you quit and stalk quickly. Also note, no need to change from friends only, you can still stalk the game and it ensures randoms won’t mess you up!
-After you have stalked your friends game, have them use the darts to hit enemies near spawn. They can even pick them up and bring them to a centralized location, but don’t scan the bodies until there are at least 5 incapacitated as the host will get chased by the figure..
-Once there is 5 or more incapacitated enemies, scan the targets. Have host be ready as the figure will likely come after the first couple of scans. Recommend hiding on a roof prior. Note that if you scan bodies back to back too quickly, it may not award the full 100, so be careful.
This should net you the achievement, but if you messed up, either reset or help the host search for more darts or sleep traps so they can incapacitate more targets for you to scan. You can record broken doors or the host, but it doesn’t give you many points at all so unless you’re close, the figure will likely get them before you finish. Also, if your friend needs the achievement for kicking a stalker, now is a good time assuming your achievement popped.
Pro tip: If a random does join and ruins it, have the defeated stalker rejoin the game as a coop and finish the game and he can pick up a Stalker dossier for the defeated Stalker 😆Also, if host dies, you should be able to pick up your dossier from the hideout to use again on the next run. You can purchase them in the van menu using snacks if you need more.