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