Here is the full list of all 20 Three Twenty One achievements.
Complete the game
Visit the PT area
Leave everything behind
Listen to the radio
Play Void
Fail CodeCrashers
Read through the viking book
Examining the football picture in the bedroom
Taking the bear in the text adventure
Finishing Castle without dying
Collect all the books
Find the secret space room
Use the printer in the text adventure
Taking the letter
Take the horse with you on the boat
Read through the friend book
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