Here is the full list of all 41 Helheim Hassle achievements worth 1,000 gamerscore.
Find every soul coin.
Be a bad Bjørn.
Finish Prologue.
Assemble The Belt Of Secrets.
Help out Fenris.
Survive the fight with Pesto without taking damage.
Buy everything in Stonemart.
Change your appearence in every slot.
Drink every smoothie.
Find Idunn.
Find the souvenir in Einar's Crazy Puzzle Extravaganza.
Win every race with Erica.
Learn every song.
Become the God of Puzzles.
Find all the gold.
Who's a good Bjørn?
Solve every puzzle.
Find every letter.
Fully decorate your house.
Gain access to the Laughter Gland.
Try out every limb combination.
Listen to everything Modgunn has to say.
Give feedback.
Give the fountain enough money.
Finish the main story.
Let poor Andre know you're okay.
Finish Helheim City.
Finish Winterberg County.
Finish Entrance County.
Climb to the top of Polyester Peak.
Send Mike Cobbles to Hell (in a nice way).
Help every stone person.
Be disappointed.
Single-handedly save the indie-puzzle scene.
Find a soul coin.
Have three heads on you at once.
Finish Riverrum County.
Pick every berry after the prologue level.
Throw and catch Bjørn's head 5 times without dropping it.
Pet every animal.
Have a gamer moment and get every achievement for Helheim Hassle.