Full list of all 78 For The King achievements. It takes around 80-100 hours to unlock all of the achievements in the base game on Windows.
The base game contains 72 achievements, and there is 1 DLC pack containing 6 achievements.
Kill 10 enemies with Firearms
Use 100 herbs
Unlock 20 items from the Lore Store
Kill 30 Fishfolk
Honor 15 Stone Heros
Break a weapon
Defeat the Old One
Defeat Vexor on Apprentice
Reach the top of Harazuel
Purge the Buried Temple
Defeat Lucky
Defeat the Hangman
Fly in the Air Balloon
Clear both Demon Caves
Solve the King's Maze
Have 1500 Gold
Defeat the Royal Droll
Kill the Kraken
Use 10 candies
Defeat the Bandit King
Defeat the Foul Priestess
Defeat Coal Heart
Unlock 1 item from the Lore Store
Defeat the Lich's Crypt
Get killed by a suicidal enemy
Kill a thief attempting to flee
Defeat the Mind Bender
Defeat Disciple
Clear the Forgotten Cellar
Defeat 3 Triclops
Have 300 Gold
Clear a Cave
Purge the Glittering Mines
Honor 3 Stone Heros
Defeat the Cultist Camp
Complete 1 Side Quest
Revive a party member
First party wipe
Clear 5 Sea Caves in 1 game
Defeat Vexor on Journeyman
Defeat Vexor on Master
Clear the Flooded Crypt
Escape the Mage Dungeon
Survive the Lava Dungeon
Defeat the Chaos Beast
Complete 50 Side Quests
Have 5000 Gold
Honor 50 Stone Heros
Kill 1000 Enemies
Defeat 100 Beastmen
Smash 150 Skellys
Murder 30 Hags
Defeat 10 Mimics
Topple 15 Crag Monsters
Crush 25 Imps
Unlock 40 items from the Lore Store
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
Defeat Deimos
Enter Hildebrant's Cellar
Reach the bottom of Hildebrant's Cellar
Reach the Inferno
Win a game of Gold Rush
Find Bradach's Cabin
Purge all 4 Water Temples
Find Captain Greenbeard's Ship
Defeat the Sea King
Defeat the Songstress