How to Beat Bonemass, Valheim's Third Boss

Buried in the foul mist of the Swamp biome, Bonemass is the third Forsaken altar Valheim throws at you. Picture a hulking mound of bones glued together with poisonous slime and you have the general idea. He hits hard, calls reinforcements, and turns the air around him into a death cloud. Here is how to find him and put him back in the ground.

Tracking Down the Summoning Altar

Bonemass does not pin himself on your map out of courtesy. To unveil his Forsaken altar, you need to dive into Sunken Crypts, the skeleton-filled dungeons scattered across the Swamp. Once you stumble across the altar inside, its location locks onto your map automatically.

The ritual itself asks for ten Withered bones, which drop from the skeletons inside those same crypts. Place them on the altar and the summoning begins.

Gear Checklist Before the Fight

Every one of Bonemass' attacks deals Poison damage, so Poison resistance is non-negotiable. Brew Poison resistance mead before you head anywhere near the altar. Pack stacks of healing food and stamina food too, because this is a marathon rather than a sprint.

For weapons, blunt damage rules the Swamp. Bonemass and the slimes he calls in shrug off slashing and piercing, while maces and clubs land for full damage. An iron mace is the sweet spot if you have the materials to craft one.

Reading His Three Attacks

Bonemass keeps his moveset short and brutal:

• Poison cloud. He winds up, then releases a green fog that lingers around his body and chips at anyone caught inside.
• Melee swipe. A heavy arm strike that punishes anyone hugging his hitbox at the wrong moment.
• Goo summon. He tears a glob off his torso and throws it, spawning skeletons and slimes wherever it lands.

The goo summon is your golden window. While he leans back to pull the ball from his body, he is wide open. Sneak in a few heavy hits, then back off before the spawned mob lands on top of you. Ranged shots are also useful when he is mid-pursuit, since he barely reacts to arrows in his back.

Winning the Fight

The recipe is simple in theory: stay above half health, step out of the poison field, and chip away during his telegraphs. Reposition constantly so the muddy terrain works for you instead of against you. Going in solo is possible, but bringing friends shortens the fight a lot and gives Bonemass more targets to worry about.

Down him and you walk away with the Wishbone, the key to finding the next biome's secrets and, eventually, the next boss.