Here is the full list of all 23 Iron Danger achievements.
Hunt down and slay all of the trolls in Bleakshore.
Blow yourself up by shooting explosive arrow while on fire.
Find and read the recipe in Kalevala.
You successfully completed Iron Danger. Congratulations!
Take a troll into the Northlander camp.
Destroy all three gates leading into the Northlander camp.
Use Earthquake while boosted by fire.
You found the fifth Shard. Your enemies tremble before you.
You put the Tyrannogrouse out of its misery.
You healed the wounded Tyrannogrouse.
Collect 30 mushrooms.
You found the fourth Shard, and it eases your pain.
Kill the alpha Roosterfish in the temple under Rimfeden.
Eat roosterfish roasted over campfire.
Grow stealth grass 20 times.
You found the third Shard, and it makes you shiver.
Defeat 100 enemies.
Kill 30 keyus.
You found the second Shard and feel the nature's call.
Die 100 times.
Collect 20 berries.
You found the fabled Healer of Brumehead.
You found the first Shard poking through your chest.