This sling is made of leather that has been blackened by fire.

This +1 sling imbues stones launched from it with an explosive charge. When you hit a target with a stone fired from an explosive sling, the stone explodes, dealing an extra 2d6 points of fire damage to the target (no save). In addition, each other creature within 10 feet of the target creature when the stone explodes is engulfed in flame from the burst of fire and takes 2d6 points of fire damage (Reflex DC 22 negates).

Prerequisites: Craft Magic Arms and Armor, fireball.
Cost to Create: 18,000 gp (plus 300 gp for base item), 1440 XP, 36 days.