Bakha

In Egyptian mythology, Bakha (also spelt Bakh, Buchis, and Bukhis) was the manifestation of the a deification of Ka (power/life-force) of the war god Menthu, worshipped in the region of Hermonthis. The name is simply Ba-Kha, which is a reference to the Ba and Akh (Akh is sometimes referred to as Khu), the components into which the Ka was split, after death (a characteristic of war). As Ka is also the Egyptian word for cattle, Bakha was said to manifest in a living bull, which, since Bakha was an aspect of a war-god, was said to be a wild bull, since these are aggressive when slightly provoked.
See more at Wikipedia.org...

[Egyptian] The sacred bull of Hermonthis in Egypt, and an incarnation of Menthu, a personification of the heat of the sun. He changed color every hour of the day.

Pacis or Bacchis (Greek) Bakha (Egyptian) The sacred bull of Hermonthis. Although not so celebrated as Apis and Mnevis, he was styled the bull of the Mountain of the Sunrise (Bakhau), and the lion of the Mountain of the Sunset. Like Mnevis he was depicted with the solar disk between his horns, the reference being not to the cosmic energy of the spatial Deeps represented by Mnevis, nor to the lunar energy represented by Apis, but to the opening (sunrise) and the closing (sunset) of the solar system.