Bull is the largest among the eight ninken of Kakashi Hatake. He is a dark-furred bulldog with an imposing build and a spiked collar. He wears the pack's standard gear: a blue vest with the Heno-Heno-Moji symbol and a Konoha headband on his left front paw. By nature, Bull is noisy, but gets along well with Pakkun, letting him ride on his head.
In battle, Bull, like the rest of Kakashi's dogs, relies on his heightened sense of smell. He tracks scents with ease, can speak, travels across water, and operates as part of the pack. Through the Earth Technique: Tracking Fang, he can move underground by a target's scent, and upon finding it, latches on and holds it, giving his master time to strike. The pack uses nimble and powerful limbs in various offensive and defensive formations.
To summon Bull, an active contract is required. The user applies blood to the palm, forms five hand signs, and presses the hand to a surface. The amount of chakra invested determines the number of dogs that appear. Bull can be called alone or together with the other ninken.
