After visiting combat chamber 3 my whole Backpack inventory is blank and all side attachments are removed, only raw backpack is left. I suspect this bug happens after you light up a combat chamber door as you know there a two torches requested to open that door but if you light up only ONE and then leave to other level for the mine for some reason backpack is voided it happened to me two times because i had not enough supplies to attend combat chamber and decided to return but because of that i lost my stuff...