The Blue Ogre is first encountered outside of Ninetails' fortress on Oni Island during Amaterasu's quest there. It is encountered alongside a Red Ogre, like it always be. The Blue Ogre is a muscular, centaur-like demon, with a large horse or ox-like body of blue muscle. It has hooves and a black horse tail, and a piece of straw is worn on each of its hind legs. For combat, the Blue Ogre wields a pair of giant sickles. However, the Blue Ogre's most prominent feature is its iron mask. The mask is of a rectangular shape with a rounded top, adorned with the face of the ogre itself. It has four fangs protruding from a wide open mouth, and a single horn on the forehead. Behind the mask is the ogre's true face, which is very similar to the adorning of the mask.
The Blue Ogre, even though a beast of savagery, has well-valued fangs which make it much more popular than its crimson counterpart. A story regarding them has a line that suggest how to obtain their treasured fangs.
"Blue Ogres are more popular than their red cousins due to their beautiful fangs.
There is a famous story which contains the line 'A lightning strike makes one bear their fangs'."
The Blue Ogre always emerges in battle alongside a Red Ogre, so in combat, Amaterasu must keep her eyes on both demons so that the highest amount of Yen and items or treasures can be obtained. The first thing must be done to defeat the Blue Ogre is using Veil of Mist so that Amaterasu can get to the demon's side and farm it from there with Golden Fury, Brown Rage and the Thief's Glove (the hidden strike glitch is not necessary, as the Blue Ogre is very damage resistant) while assaulting it at the same time. When enough damage is dealt, the demon will be stunned, and Amaterasu can use Power Slash to destroy its mask, rendering it vulnerable from all angles. The demon will also occasionally lifts its mask and blow a cloud of poison at Amaterasu, which then she must use Galestorm to deflect the poison and stun the demon, giving her a chance to destroy its mask. The Blue Ogre will also attempt to attack Amaterasu by engulfing its giant sickles in poison, and swing them at Amaterasu. This is when she must timely execute a Sub-Reflector Counterattack to farm a Demon Fang, although she would not execute the pile-driver on the Blue Ogre. Other attacks of the Blue Ogre include a rushing attack, a sickle slam that sends a wave of earth straight ahead, and a plunging dive from the air that also creates a small shockwave. When the Blue Ogre is killed, use Thunderstorm as its Floral Finisher.