Bonemass

Bonemass is a giant mound of mud, bone, and rot sitting in the Swamp. It is the first real wall in Valheim: it hits hard, it poisons you, and it has a huge health pool. Come prepared and it is very doable.

Summoning Bonemass

You need 10 Withered Bone to summon it. These come from the Sunken Crypts you unlocked with the Swamp Key, usually piled in bone heaps you break with a pickaxe, and from Muddy Scrap Piles.

How to Beat Bonemass

This fight is about damage types. Bonemass is resistant to slash, pierce, and poison, and weak to blunt, so a mace is roughly double the damage of a sword here.

1. Drink a Poison Resistance mead right before you start, and keep refilling. Its poison cloud is what actually kills most players.
2. Use an Iron Mace (or Frostner later) and hammer it between its swings.
3. When it belches the green poison cloud, back out, wait, then come back in.
4. Pop the Eikthyr power to reposition fast, or Bonemass's own power on a later attempt for a damage shield.

Bring more meads than you think you need. The fight is a slog, not a burst.

Drops and Reward

Bonemass drops the Wishbone and the Bonemass Trophy. The Wishbone is a game-changer: equip it and it pings when you are near buried treasure and Silver veins under the Mountains, which is how you find silver to mine.

The Bonemass power gives a big resistance to blunt, slash, and pierce damage for a short window. Save it for tough fights and other boss attempts.