Here is the full list of all 22 Strangeland achievements.
The Stranger escaped Strangeland.
The Stranger died fighting.
The Stranger killed himself.
The Stranger jumped.
Talked to all the major characters.
Got the final knife.
Died every possible way.
Exited the Hall of Mirrors.
Reached the Hall of Mirrors.
Correctly identified the Young, Middle Age, and Old Strangers.
Got Tooth.
Killed the Crab.
Resisted opening the box.
Heard all the Clown's jokes.
Gathered all the spirits using the torch.
Persuaded Nineveh to hone Beak.
Opened the box.
Released the Dark Thing.
Lasted as long as Rosencrantz and Guildenstern.
Got Beak.
Won the Shooting Gallery on the highest speed.
Starting Out.