Here is the full list of all 38 Hard West 2 achievements.
Maxed out loyalty with Old Man Bill.
Killed 60 Hellspawns.
Finish "The Great Train Heist" in no more than 10 turns with all objectives completed.
Completed a mission using only Handguns.
Completed a mission using only Shotguns.
Completed a mission using only Rifles.
Finished the game on the Easy difficulty.
Finished the game on the Hard difficulty.
Finished the game on the Nightmare+ difficulty.
Finished the game on the Normal difficulty.
Finished the game on the Nightmare difficulty.
Completed all world map side objectives in Chapter 3.
Finish "One Last Ride" in no more than 12 rounds with all objectives completed.
Killed 666 enemies.
Visited every location in all Chapters.
Collected every card in the game.
Form sets of Royal Flush with 4 posse at the same time.
Maxed out loyalty with Clalish.
Form sets of Full House with 4 posse at the same time.
Form sets of Straight with 4 posse at the same time.
Maxed out loyalty with Laughing Deer.
Finish "Wanted: Lady Shrike" in no more than 15 turns with all objectives completed.
Killed 50 Shadow Dancers.
Maxed out loyalty with Lazarus.
Finish "Riftwalkers" in no more than 10 turns with all objectives completed.
Finish "A Plague Upon This Land" in no more than 12 rounds with all objectives completed.
Killed 80 Revenants.
Finish "3:10 To Heaven" in no more than 1 round with all objectives completed.
Completed a mission using only Melee weapons.
Maxed out loyalty with Flynn.
Completed all world map side objectives in Chapter 1.
Finish "Flynn's Vision" in no more than 10 turns with all objectives completed.
Finish "O'Kane Farm" in no more than 8 turns with all objectives completed.
Finish "Frostbitten in Calla Calla" in no more than 10 turns with all objectives completed.
Finish "Blasting Out" in no more than 8 turns with all objectives completed.
Killed 100 Bandits.
Finish "Fooling The Hangman" in no more than 4 turns with all objectives completed.
Finish "Daredevils" in no more than 8 turns with all objectives completed.