Me and my friends had the most crazy boss battle – considering we glitched the elder into a position where he wasnt moving or attacking. We just shot arrows at him.
But bonemass….
We had to fight him in the bloody plains. Each of us died 3 times – it was a matter of hopping in the portal and getting our stuffs and continuing the fight.
Why bonemass got into the plains? we were fleeing. our portal was in the black forest- otw to the swamp there was a kind of a small area of plains. -.- we thought it was the meadows and went on –
we got killed by those flying abominations (deathsquitos) – a cow on steroids (lox was it?) and bloody fullings – thankfully we got a serpent shield so we didnt die immediately but still- once our stamina was down we definitely died.
but at the end of it was sweet sweet victory. never fight a boss in a different biome – ours lasted 2 hours. Im sure the next boss aint gonna be as tough as this one… right?
Source: https://www.reddit.com/r/valheim/comments/piwond/our_crazy_experience_with_bonemass/
