Here is the full list of all 69 Diehard Dungeon achievements.
Obtain Lightfoot ability.
Defeat Hive Mind.
Obtain Reflex ability.
Obtain Kaboom ability.
Obtain Heavy Duty ability.
Obtain Heartbreaker ability.
Attain Legend rank.
Attain Champion rank.
Attain Hero rank.
Obtain Pierce ability.
Defeat 2000 enemies.
Attain Slayer rank.
Defeat Giant Oaf.
Attain Adept rank.
Obtain Looter ability.
Defeat Mr Illusion.
Pickup 100 hearts.
Use 50 tokens.
Destroy 1000 containers.
Attain Valiant rank.
Obtain Trigger Happy ability.
Obtain Sense ability.
Obtain Iron Grip ability.
Have 20 tokens.
Escape the dungeon.
Open the gold chest.
Defeat Zombie Chest.
The Companion Chest upgrades to its maximum level.
Obtain Voodoo ability.
Destroy 300 lights.
Attain Warrior rank.
Collect 10,000 treasure.
Obtain Slash ability.
Win a Trapdoor game.
Obtain Forget-Me-Not ability.
Obtain Vision ability.
Obtain Fireproof ability.
Obtain Attract ability.
Obtain Knives ability.
Obtain Courage ability.
Obtain Toasty ability.
Defeat Evil Chest.
Attain Fighter rank.
Obtain Scatter ability.
Obtain Triple Shot ability.
Obtain Mithridate ability.
Obtain Houdini ability.
Obtain Repel ability.
Attain Diehard rank.
Defeat the Dungeon Master.
Escape the dungeon in Champion Mode.
Use 20 Teleporters.
Obtain Dash ability.
Defeat Stumpy.
Avoid opening 10 chests.
Avoid picking up 20 hearts.
Destroy 20 chests.
Achieve rank 10 in Mayhem.
Defeat 200 enemies by setting them on fire.
Destroy 500 containers with fire.
Survive 20 rooms of Survival
Escape the dungeon at Diehard rank, in Champion Mode, and defeat the Dungeon Master.
Complete Fading Light in under 3 minutes.