Currently any slain mob will 'explode' when killed, dropping their loot. This is fine for a lot of kills as you can pick the loot up from the ground.
However for mobs like Sea Serpents the only viable strategy is to harpoon a living Serpent, drag it to shore to then finally have the ability to loot.
My idea is that instead of mobs 'exploding' when killed, instead, a corpse of the mob is left behind which can be manipulated by the player e.g. Harpoon. Players would then be able to press 'E' to loot and the mob would 'explode' as it currently does.
This could also open up the opportunity of being able to get more resources from mobs if you drag them back to your base for processing, e.g. a butchers table for more meat or a skinning rack for more hide.
Just an idea I had whilst going insane farming Serpent meat.
Source: https://www.reddit.com/r/valheim/comments/pta4o6/idea_persistent_mob_corpses/