Here is the full list of all 27 Forgotten Hill Disillusion achievements.
Welcome in Forgotten Hill Museum
Make your new friend drink
Get killed by a bug
Show the ticket for the Flora & Fauna section
Deliver the precious bird
Show the ticket for the Sea Mysteries section
Deliver the tasty fish
Show the ticket for the Sculptural Art section
Put some good music on
Travel to a different reality
Feed a stone monster
Send a crazy psycho to hell
Use the scalpel properly
Send a stinky crawfish to hell
Make a scarecrow
Send a wicked old bat to hell
Use the legendary sword
Send a mad killer to hell
Get yourself killed
Kill the guard
Collect all documents
Get out!
Get out and save some Nynchkuddys
Get out and save every child
Do not steal
Make the first step in your future occupation
Complete the game without using any hint