Snark wasn't really an impressive Goblin. He was quick, but others were quicker. He was strong, but others were stronger. He was smart, but others were smarter. He was small, and well he was small, smaller than any of the other full grown Goblins. They always picked on him: They would tie his big ears together while he slept, throw creepy-crawlies at him and one time even set his bed on fire. His only friend was his toad Croaks, the 14th as the other Goblins had killed all his predecessors.
When he had enough of the bullying Snark would always sneak off in the night and vanish for a few days before returning. Once, on what he considers a fateful night, he came across a scene on the road: A small caravan of humans was being attacked be ferocious Orcs, it was further away from home than he had ever been. Snark looked on from a distance, appreciating the scene. Eventually the Orcs killed all the humans and they took the bodies of the people, and of the horses, with them. Seeing this as his chance Snark ran out into the wreckage to scavenge and there he found it: A battered old musket. Clearly those idiot Orcs with their empty brains had stamped on it as it was broken. But Snark was smart and he could fix it. It was his lucky day though, as among the wreckage he also found a small chest which contained the tools he needed, or figured he needed, to repair it. Mumbling his thanks to great Zogmugot, Snark went to work.
Several days later he made his glorious return. The gun worked. First the Goblins that always bullied him laughed when he returned, hands all black and sooty smudges in his face, but they stopped laughing when Snark shot them in the foot. Now they leave him alone, afraid he'll shoot other bits as well.