Spear of Goblin Destiny (3.5e Equipment)
From D&D Wiki
It appears to be made of bamboo, and has a curiously shiny blue rock strapped to the tip. It might actually be a gem of some sort, if the quality wasn't so poor.
You are traveling in particularly dark woods. These woods have been a bane to travelers lately. Suddenly, you see movement in the forest. It appears to be a group of goblins. You laugh to yourself at their crude weapons and armor. One of them, apparently the leader, moves towards you. You are fairly certain it is being pushed by its comrades, and it is the smallest of the group. As he stabs his spear at you without fanfare, you notice the tip is not just a rock...
This spear was found by a particularly cunning goblin (if a little small). It was "blessed" with a gem head by some prankster god, and while magical, gives a bonus to damage only. This applies only in the hands of goblinoids.