Here is the full list of all 52 Puzzle Agent 2 achievements. It takes around 2-3 hours to unlock all of the achievements on Windows.
Find at least 25 pieces of gum in Scoggins.
Discover a buried secret somewhere in the woods.
Decode the mysterious note.
Meet Scoggins' local anthropologist, Alfred.
Get a room for Nelson's 'vacation' to Scoggins.
Spend over $202,259 of taxpayer dollars; The number of Christmas trees cut in Minnesota in 2007 (source: USDA).
Return to Scoggins, Minnesota.
Find out the secret Olav locked away in his cabin.
Discover Korka's theory about the missing people of Scoggins.
Discover a top-secret piece of space equipment.
Find the factory foreman, Isaac Davner.
Complete the case in Scoggins, Minnesota.
Complete Puzzle Agent 2.
Earn the perfect rank of "Puzzle Agent" after completing all puzzles.
Return from the madness of space.
Keep Nelson in perfect focus while running towards Lake Svenz.
Complete all puzzles in the Scoggins case.
Complete all bonus puzzles unlocked after completing the game.