Didn't spend a whole lot of time gathering copper and tin from their respective deposits, but I filled the storage of my Karve and what i could carry. Go me. Get to home base where the magic happens.. Lay copper in the smelters and head up to the tent for some shut eye. GOOD DAY! Soon as I lay down in my small (albeit) comfy bed and get my dream excerpt game crashes..
Oh well load it back up and get back to it, right? Wrong. Load up the save and i'm back in my little starter shack I had been at prior to this excursion? Odd. I still have some copper on me. Go check for the boat, gone.
Quickly, I drop off the copper in a storage bin and take a portal to home base, no copper in smelters, no bueno, run off to the dock and its already a dismal sight as I don't see the mast of my Karve. Instant disappointment.
(edited: Forgot to mention Karve is nowhere to be found)
Moral of my pain.
Save. Your. Files.
Source: https://www.reddit.com/r/valheim/comments/12g5mgo/psa_always_remember_to_save/
