Here is the full list of all 22 Clue/Cluedo achievements.
Play your first game
Uncover your first Clue
Play 5 Online Multiplayer Games
Play an Online with Friends Game
Play 5 Clue Cards Games
Play 5 Master Detective Games
Ask 3 Key Questions
Play a game with the Clue Sheet Assistance set to Off
Play a game with an alternative customization item equipped
Win a game with an alternative Token equipped
Win a Single Player game in Hard difficulty
Win 20 Games
Complete the (Tudor Mansion) Case File
Uncover all (Tudor Mansion) Case Clues
Uncover all (Tudor Mansion) Weapon Clues
Uncover all (Tudor Mansion) Room Clues
Uncover all (Tudor Mansion) Suspects Clues
Complete the (Black Adder Resort) Case File
Uncover all (Black Adder Resort) Case Clues
Uncover all (Black Adder Resort) Weapon Clues
Uncover all (Black Adder Resort) Room Clues
Uncover all (Black Adder Resort) Suspects Clues