So i had the same thing happen to my main character when i played through BoW. After checking into my thread in Steam about it and after a response i realized i had bought the necklace from the Deck of many Things. Right after i bought it and equipped it i didn't play for a few days. So when I started to play BoW the same exact thing happened to me. Check your save when you started BoW and see if you had that necklace on. I thought it would be an extra summoned attacker not change my own weapon when I got it. I never made the connection. Hopefully that was your issue to and not a bug.
Keep up the good work guys. Pillars is a breath of fresh air since BG,IWD, and NWN.
Prometheus
Paladin
Herald of Berath
