[WFRP] Magic Sling: Thwacker
Thwacker is a magic sling that gives a +10% bonus to its wielder's Ballistic Skill. Any stone slung by Thwacker gains +1 to damage, and any creature subject to Instability* must make an immediate check to see if they have become unstable (a 6 on a d6).
Instability rules can be found in the WFRP book, page 215
*Undead include Carrion, Skeletons, and Zombies. For more creatures, see Ethereal Undead, Demons, and Elementals.