1) Load the save
2) Go to the civilizations screen
3) Find any site belonging to "The Glens of Sport" Elven civilization, for example the cave 12 tiles south 7 tiles east of the fort, or one of the Elftowns 8-9 days to the northeast
4) Create a mission to raid the site (Reproduced it with "Razing" detail)
5) Assign The Shields of Crushing squad and start the mission
6) Wait for the squad to return
7) Game crashes most of the time a second or two after the squad returns