The description for Wahai Poraga pollaxe I just found in the Undercroft reads:
System.ArgumentNullException: Argument cannot be null
Parameter name: key
Then it has its actual flavor text. Also the tooltip doesn't appear for this weapon.
I'm on the latest mainstream patch, and I verified the game data through Steam.
I can provide the information listed on the stickied post, but file attachment size is currently limited to 0.5MB; too small for savefile of 2 MB.
I will provide screenshot and savefile through whatever means is requested.