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