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Please note that some of the images on this page are out of date since Bonemass was visually updated with version 0.153.2

Bonemass is a boss in Valheim.



"Wanderer, look to your feet, that tread upon our tomb. One thousand bones without their meat, will drag you to your doom."


Bonemass' summoning altar is found in the Swamp biome. His location can be found when visiting Sunken Crypts, where a Vegvisir will reveal the Forsaken altar on the map. The Runestone can also be found at stone tower ruins in the Swamp biome.


Ten (10) Withered bones must be used at the Forsaken altar to summon Bonemass.

Attacks & Abilities

Bonemass uses three different attacks:

  • A close-range swipe at a player dealing up to 80 Blunt and 30 Poison damage to players, and 1000 Chop and 1000 Pickaxe damage to any trees or rocks hit.
  • Summon minions: At intervals, Bonemass will reach into his armpit to throw out a glob of goop. This is never directed at a player, and will spawn up to 4 random monsters (skeletons and/or blobs) where it lands. No more of a creature type will be spawned once 8 of that type are already present.
  • Bonemass will charge up with a thick green cloud before releasing a wave of poisonous ooze, poisoning everything in a wide range around him (100 Poison damage). This is signaled when he leans backwards. The poison cloud persists for several seconds and will continuously refresh the poison duration on any player that stays inside.
  • Environment aura that forces raining which means pulling him from the swamp can't be used to remove Wet.


Dealing with its attacks

  • The fight is balanced around the expectation that players will use Poison resistance mead which reduces poison damage by 75%. Not doing so can be very dangerous, and would require prior experience with the fight to avoid being poisoned.
  • Summon minions: If the minions are not prioritized they may overwhelm the player. Bonemass' armpit glob summon is generally aimed away from players and has a very slow animation, during which it is vulnerable to attack. Alternatively the player may prefer to back up and prepare to attack the spawned creatures the moment they land. The Stagbreaker and Iron sledge are very effective for this.
  • Poison Cloud: To completely avoid this attack, players in melee range may need to start running away immediately when it looks like Bonemass is about to sneeze. Rolling can be too slow and drains more stamina than running.
  • Melee: Very strong and poison-inflicting, normal blocking will likely stagger the player and inflict the leftover damage. Can be parried, or dodged using the brief invincibility of rolling. It can also be avoided by sprinting out of range.

Damage types

  • Bonemass and its minions are weak to blunt damage and resistant to almost everything else. Players wanting as short of a fight as possible will want to use clubs.
    • Frostner is the ideal weapon for fighting Bonemass due it dealing both blunt and frost damage. It is theoretically possible to craft it prior to fighting Bonemass but finding the required silver is extremely difficult without the Wishbone.
  • Pierce damage (including bows) is extremely ineffective. Of the available arrows, Frost arrows are somewhat effective, but requires mountain exploration to gather the required Obsidian and Frost glands from Drakes.

Other strategies and notes

  • Using a hoe to level out and/or raise the area around the summoning altar will serve the dual purpose of allowing better mobility for the player during the fight and also preventing leeches from interfering with the fight.
  • Having multiple Medium healing mead and high health Food may be desirable.
  • Use of Eikthyr Power can be desirable to reduce stamina drain from running and jumping.
  • Crafting a hundred or so frost arrows and shooting Bonemass from up high in the trees is a safe and easy way of defeating Bonemass. Some spawn locations may have a large stone tower that can be accessed as well.

Group strategies

It may be ideal to have most players focused on killing the skeleton and blob spawns as soon as they land. While there is a cap on how many minions Bonemass can have spawned at once, it is very high at 8 Skeletons and 8 Blobs.

If the group is 3 or more players with a preference for bows, a ranged strategy can still work even without frost arrows. Despite the boss's resistances, the groups constant, combined damage can whittle it down fairly quickly. Players should spread out from each other so that only the one player Bonemass is currently chasing needs to run away. Minions should be focused as soon as they spawn, ideally switching to blunt melee damage to kill them quickly, and then swap back to bows for Bonemass.


Defeating Bonemass provides the player with a Wishbone, which is practically required to locate Silver Deposits beneath the surface of the Mountain.


Item 0 Star
Bonemass trophy.png Bonemass trophy 1
Wishbone.png Wishbone 1 per player

Forsaken Power

Bonemass power provides a large amount of physical resistance for 5 minutes.


Defeating Bonemass affects the following events for that world:

  • Disables: Draugr and Skeleton "A foul smell from the swamp".
  • Enables: Blobs and Oozers "A foul smell from the swamp".
  • Enables: "Skeleton Surprise".
  • Enables: "A cold wind blows from the mountains" (if Moder hasn't been defeated).
  • Enables: "There's a smell of sulfur in the air" (if a Surtling has died).
  • Enables: "You are being hunted".

Creature Spawning

Defeating Bonemass unlocks Skeletons to spawn at night in the Meadows, Black Forest, Swamp (additional), Mountain and Plains. They can only have 0 stars.



Passive CrowDeerFishGullLeviathan
Meadows DeerBoarNeckGreyling
Black Forest GreydwarfGreydwarf bruteGreydwarf shamanSkeletonGhostRancid remainsTroll
Swamp SkeletonDraugrDraugr eliteLeechBlobOozerSurtlingWraithAbomination
Mountains WolfDrakeFenringStone Golem
Plains DeathsquitoFulingFuling BerserkerFuling shamanGrowthLox
Ocean LeviathanSerpent
Ashlands Surtling
Deep North
Boss EikthyrThe ElderBonemassModerYagluth
Spawners & Boss Minions Rancid remainsBody pileRoot
NPC HuginHaldorHalsteinOdin