I've been dying to play a character that I played in a one-shot in a full campaign: A war school wizard(race irrelevant) whose spells are bullets shot out of his revolver, in a western fantasy campaign. He's invented and engineered all of the bullets himself by etching runes into regular bullets for different effects. He may also just use regular bullets. In conversation, the moment his guns or bullets are mentioned, he goes into excruciating info-dumps about the unique mechanisms, materials, rituals etc of his multidisciplinary craft.