Full list of all 56 For The King achievements worth 1,000 gamerscore. It takes around 60-80 hours to unlock all of the achievements on Xbox One.
Defeat Coal Heart
First party wipe
Clear the Forgotten Cellar
Defeat the Hangman
Defeat the Mind Bender
Defeat Disciple
Defeat the Lich's Crypt
Defeat the Royal Droll
Kill a thief attempting to flee
Defeat Deimos
Purge the Glittering Mines
Revive a party member
Defeat the Cultist Camp
Clear both Demon Caves
Defeat Vexor on Apprentice
Defeat Vexor on Journeyman
Defeat Vexor on Master
Solve the King's Maze
Purge the Buried Temple
Clear 5 Sea Caves in 1 game
Clear the Flooded Crypt
Escape the Mage Dungeon
Survive the Lava Dungeon
Defeat the Chaos Beast
Break a weapon
Complete 50 Side Quests
Have 1500 Gold
Have 5000 Gold
Defeat Lucky
Defeat the Bandit King
Defeat the Foul Priestess
Defeat the Old One
Honor 15 Stone Heroes
Honor 50 Stone Heroes
Kill the Kraken
Smash 150 Skellys
Topple 15 Crag Monsters
Unlock 20 items from the Lore Store
Unlock 40 items from the Lore Store
Reach the top of Harazuel
Slay the dragon at the top of Frostbite Peak
Defeat the Yeti, free her "prisoner"
Unlock the armory
Break a sieged town
Kill 5 Snowmen
Help Hildebrant retrace his steps
Use 100 herbs
Use 10 candies
Reach the bottom of Hildebrant's Cellar
Reach the Inferno
Purge all 4 Water Temples
Defeat the Sea King
Kill 10 enemies with Firearms
Defeat the Songstress
Find Captain Greenbeard's Ship
Win a game of Gold Rush