Here is the full list of all 12 Red Johnson's Chronicles - there are 1+2 - there are Steam Special Edition achievements.
Solve the first riddle
Win your first QTE
Kill every target without wasting a bullet
Solve every riddle
Win every QTE
Open every mailbox
Complete the game
Win every riddle in one try
Win every QTE in one try
Complete the game with Rank A
Complete the game with 100% progress
Complete the game with 100% progress in record time