Here is the full list of all 38 Psychonauts trophies - there are 21 bronze, 12 silver, 4 gold and 1 platinum.
Unlock all trophies.
Complete Meat Circus.
Achieve Rank 101.
Sort all Emotional Baggage.
Gather all Figments.
Crack all Vaults.
Redeem all 16 Scavenger Hunt Items.
Complete the Punchy Target mini-game.
Find Edgar's Secret Garden.
Revisit all brains after completion.
Achieve Rank 80.
Buy an item from the Camp Store on Christmas.
Introduce all Camp Kids to Mr. Pokeylope.
Re-brain the Children.
Complete The Asylum.
Complete Black Velvetopia.
Find all Golden Helmets.
Earn all Merit Badges.
Complete Gloria's Theater.
Achieve Rank 60.
Complete Waterloo World.
Complete The Milkman Conspiracy.
See yourself through the eyes of many others.
Complete Lungfishopolis.
Achieve Rank 40.
Cook and consume two different kinds of roast in one sitting.
Spy on Bobby's love life.
Hear Vernon's Ghost Story.
Complete Milla's Dance Party.
Uncover Milla's Secret.
Give the Coach's speech on the stump.
Use the bacon. A lot.
Achieve Rank 20.
Witness Maloof's transformation.
Complete Sasha's Shooting Gallery.
Discover the secret history of Whispering Rock.
Read many bulletin board messages.
Complete Basic Braining.