I was on this reddit earlier and seen a post about backpacks and had an idea If any back packs were added I'd think it would definitely have to be a tier thing with them
Leather bag gives 2 slots with no armor rating
Root one from swamp does 4 slots with a weakness to fire but resistance to Peirce (like the chest piece)
Wolf does 4 slots with frost resistance
Lox do 8 slots no armor
Padded version doing 6 but an armor of about 2 to start at level 1
This could be a balanced way for the back packs and maybe also give a +50 carry weight. this could make them a balanced addition with them taking the slot of the cape making it a decision to make on what u need for what and all with pros an cons to them an viable through a gameplay without disrupting much in terms of tons more slots or overpowered carry weight
Source: https://www.reddit.com/r/valheim/comments/12bvyzg/an_idea_about_backpacks/
