I need a confirmation on next thing i noticed:
I placed a campfire on enterance to Burial Chambers (to get rested buff) and that prevented spawn of skeletons from evil bone piles until i destroyed campfire.
It was not a big Burial Chambers (normal sized, i got 8 cores from it) but it contained 2 evil bone piles and both of them were "disabled'.
As i know – campfires prevent spawning even when they are not lit.
Haven't seen that tip in any videos on youtube. So got a next pro tip:
Place campfires in some range (not necessarily very close) to any spawners (evil bone pile etc.) to temporarily disable them. It will make exploring caves/crypts/draugr villages etc much easier. On the other hand you don't need to kill spawners but its better just keep 1 or 2 of them as source of resources, just destroy campfire and farm resources from mobs*, then place campfire again.
*Beware one or two star mobs as they are MUCH stronger.
I get rekt by two one-star skeletons spawned at once with my deer-hide armor and wooden shield.
Source: https://www.reddit.com/r/valheim/comments/tesx6d/campfire_disable_spawners/
