Grimm Saltback is a dwarven ska performer and proprietor of the Dragonback Tavern. His demand that the Dragon Friends repay their debt to him was the impetus for their first adventure. As of Season 5 they have not paid him back. In That's all Hocus Pocus, Freezo discovered that Grimm had become affected by the Rictus Plague and killed, however, this appears to have been non-canonical. In Season 5 it was revealed that Grimm had become so tired of the Dragon Friends and their broken promises to him that he actively aided the Cult of the Lampwick in resurrecting Strahd von Zarovich in the hope that he would defeat the Dragon Friends.
He plays trombone for his ska band, Grimm & The Magic Trombones, together with lead guitarist Smokey Dave Paisley, bassist One-to-Three-Tone Tony (how many tones he gets depends on if Grimm likes him), and Wolfman Jack Who Is Actually A Wolfman; although he has started other bands before.