Appearance: Moradin's Piece is a large semi-automatic pistol, heavy a slab sided and cruel as a brick. The metal is adamatine with a brushed mithril finish, and the grip has dragonbone inlays. The words 'The Peace of Moradin' are acid etched down the top of the gun in dwarven runes ended at the iron sight.
Benefits: Moradin's Piece is a masterwork heavy pistol, and has appropriate bonuses to hit and damage, as well as ignoring all non-magical armors. The gun also inflicts double damage on all Goblins, Orcs, hobgoblins, and related greenskins. On a lone Goblin the most fitting description is 'makin spaghetti sauce' Against giants, the damage increases to triple damage. Finally, when used against golems, earth elementals, and other similar creatures, the pistol can be used like a Priest's Holy Symbol to turn undead, but only affecting earth and earth related creatures.
Drawbacks: Being a gunslinger for the God of the Dwarves is a serious task, the bearer must constantly act in a manner defitting a Dwarven lord in exceptional standing to the God of the Earth. No mercy to foes, expect no mercy. Slay all goblins and giants, grant hospitality even if it means having nothing for yourself. The gun itself should have almost a will of its own, guiding and directing the gunslinger to the foes of the Earth, aiding the dwarves where needed and the like. This is a weapon of fate and destiny.
Lore: Guns are overlooked and frowned upon in Fantasy, but guns are also pretty darn cool. In a modern setting, like Shadowrun or the like there is no reason that the masterful weapons of the dwarves and the elves wont be there. Also, did it because I could and felt inspired.
Twist: Moradin is a neutral entity, so long as the bearer does right by the dwarves, it doesnt matter if he is a righteous holy warrior, murdering psychopath, or such. Moradin's Piece is also chauvanistic and will not fire in the hands of a woman.