Leon Burger

From Muppet Wiki

Leon Burger, a small pitbull, is the silent valet/henchman to Baron Von Rottweiler on Dog City. Leon never speaks, and silently abets his master in his various schemes, from minor crimes to world domination. Leon's weakness, which often leads to Rottweiler's downfall, is his love for a good game of fetch, which Rottweiler taught him. When Ace Hart or anyone else hollers "fetch," Leon cannot resist, usually returning with a live stick of dynamite or other dangerous item.