Mastiffs were a large breed of Dog, generally used as a guard and fighting dog due to their size and bite strength. Weighing up to 230 pounds, they were great at warding off intruders but were nonetheless easy to train, loyal, and highly territorial. In appearance, mastiffs were characterized by their broad chests, thick necks, and deep barks that resonated through castle halls and rugged wilderness alike.
They possessed keen senses, including sharp hearing and a keen sense of smell, which made them adept at detecting intruders or approaching dangers. In addition to these qualities, their strength lead them to be employed by Halflings and other small creatures for use as mounts.