Zenki and Goki

Zenki and Goki (前鬼 & 後鬼) are two shikigami used by Asakura Hao in his first life and later fell under the control of Kyōyama Anna.

About
Zenki and Goki are a pair of shikigami that were captured and used by Hamono Tadatomo, and Asakura Hao—during his first life—later took them as his own. They were very loyal to Hao and would kill anyone who came in their way. After being caught by Kyōyama Anna, they seem to lose their conscience.

After Hao's first defeat by the Asakura Family, they were sealed within the Chō-Senjiryakketsu from where they tried to kill anyone who attempted to learn the contents of the book. During the Shaman Fight in 2000, Tamamura Tamao accidentally released Zenki and Goki from the book, but they were quickly subjugated by Anna with her 1080 Prayer Beads and made her own.

Years after the Shaman Fight, they were inherited by Alumi Niumbirch, an itako disciple of Anna.

Zenki
Zenki is the blue shikigami. It has a large horn in the middle of its forehead and two downward pointing tusks. It is large and rather muscular. It uses melee combat as its main form of fighting and the shield it carries is for hitting its enemies. It possesses the ability to formulate simple battle plans and though it takes him some time, it consumes very little Furyoku and therefore it is easy to use. Its eye sockets are shaped like the "Seven Star Tree of Renewal".

Goki
Goki is the red shikigami. It has two large horns on its forehead and two upward-pointing tusks. Like Zenki, it is large and muscular and uses a large battle axe for combat. Although its strong point is defense, it can attack if necessary. Its eye sockets are shaped like the "Five Point Star". Unlike Zenki, it does not have eyes at each point of the star; instead, it has one in the center.

O.S. Zenki and Goki
Description: Once powerful shikigamis sealed within a parchment seal by Hao to protect the Chō-Senjiryakketsu. Now they obey Anna, who subdued these fearsome spirits and made them her Guardian Ghosts. With her mastery of the Chō-Senjiryakketsu, Anna can easily invoke the two ogres as Over Souls. Zenki is formidable at melee-combat, using only its fists while Goki wields a mighty battle axe. They are also large and very intimidating.
 * O.S. Zenki & Goki (O.S.前鬼後鬼 Zenki Gōki)
 * Shaman: Kyōyama Anna, formerly Asakura Hao
 * O.S. Type: Spirit Type
 * Spirit Ally: Zenki & Goki (Shikigamis)
 * Medium used: Paper seal doll

Anime/Manga Difference
In the original manga series, the pair were never given an official coloring. In the Kang Zeng Bang Shaman Files and the 2021 anime series both were dominantly colored black, with Zenki having blue aesthetics and Goki having having red aesthetics.

In the 2001 anime series, it is Hao who captures the two ogres. A flashback is shown, where Hao as an adult in his first life, is seen confronting and sealing them within two paper talismans.

Trivia

 * As a part of a 20th-anniversary celebration, Hiroyuki Takei put together new illustration to serve as the exhibition's key visual, one of them being spirits shown in spirit ball modes that were never shown in the series, Zenki and Goki being amongst them.
 * Another variation of the spirit ball modes were featured on the cover of Shaman King The Super Star Volume 4.
 * Zenki and Goki are named directly after two oni attendants who were said to serve the ascetic En no Ozunu, legendary founder of Shugendō.