Here is the full list of all 40 The Vagrant achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
Achieve true ending
Clear the game in Hard difficulty
Unlock all achievements
Acquire a weapon or armour with 4 runestones
Collect 1000000 mana
Acquire all skills
Unlock all abilities
Defeat Fallen Kumasith
Unlock all entries in Monsterpedia
Acquire Sword of verum
Explore all areas
Collect 1000000 gold
Acquire all recipes
Failed to defeat Shroom prime
Failed to stop Soulreaper
Failed to defeat Santiago
Defeat Soulreaper
Achieve normal ending
Unlock all entries in Note
Defeat Valerie
Slay the chicken
Defeat Shroom prime
Defeat Ground shaker
Consumed 100 potions in total
Stop Soulreaper
Achieve 999 combos
Achieve 500 combos
Slay 666 monsters
Defeat Santiago
Defeat Headless horseman
Defeat Kumasith
Failed to defeat Kumasith
Defeat Maximillian II
Keep drinking potions
Defeat HMWV
Defeat Esgonian general
Fight Soulreaper
Achieve 100 combos
Acquire a max ranked weapon or armour
Acquire an onion from the chef in Brocley village