Bellerophon's Spear (3.5e Equipment)
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Before his battle with the chimera, the gods granted Bellerophon a powerful spear to aid him against the beast. This +4 spear grants acid, cold, fire, and lightning resistance 15 against breath weapons.
Bellerophon's Spear deals double damage when used from the back of a charging mount. It has reach, so you can strike opponents 10 feet away with it, but you can also use it against an adjacent foe. While mounted, it can be wielded with one hand.
Any stone skewered by Bellerophon's Spear has its weight reduced by a factor of 100 so long as it remains pierced. Bellerophon used this spear to lift a boulder and fling it into the mouth of the chimera, which killed it.