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A slingshot has a strong pair of rubber bands attached to a Y shaped handle. The slingshot hurls lead bullets. It doesn't shoot as far as a normal sling but has the advantage of increased accuracy. It is favored by druids, halflings and young schoolboys (often to the detriment of school teachers) Your Strength modifier applies to damage rolls when you use a slingshot, just as it does with thrown weapons. You need at least two hands to use a slingshot.
You can hurl ordinary stones with a slingshot, but stones are not as dense or as round as bullets. Thus, such an attack deals damage as if the weapon were designed for a creature one size category smaller than you (for instance, 1d3 instead of 1d4 for medium size), and you take a -1 penalty on attack rolls.
Mischievous ingenuity amongest halflings and young schoolboys has resulted in improvised ammunition for this weapon (-1 penalty on attack rolls applies), including thunderstones, rotten eggs, alchemical items, tomatoes and ferrous aqua pellets.
Halflings gain their +1 racial bonus on attack rolls with a slingshot
--Mufasa 14:56, 20 May 2011 (MDT)