This article is about a/an Greeed-like entity/rider in Kamen Rider Fourze and Kamen Rider OOO.
"Do not beg for your life, it is a waste of time."
―Poseidon's boastful words[src]

Poseidon (ポセイドン) was a Greeed-like entity who posesses Michal Minato and becomes Kamen Rider Poseidon (仮面ライダーポセイドン Kamen Raidā Poseidon), and is the movie-exclusive Rider who appeared in the OOO section of the Movie War Mega Max film.



Kamen Rider Poseidon about to kill Eiji before Michal takes control.

Poseidon is a Greeed-like entity formed from the Cell Medals and Core Medals within Michal's body, turning him evil 40 years into the future. As Michal, he is given three Core Medals and the Poseidon Driver which he receives from the remnants of the Kougami Foundation in his time. He then becomes able to transform into Kamen Rider Poseidon. He then arrives to the present time in Michal's body to eliminate all Kamen Riders. The Kamen Rider Poseidon entity is eventually split from Michal's body in his Kamen Rider Poseidon form.

Kamen Rider Poseidon was defeated by Kamen Rider OOO Tajadol Combo's Providence Drop and Kamen Rider Aqua's Oceanic Break, with his Core Medals taken for Kannagi to transform into the Super Galaxy King.

Kamen Rider Brain

Evil Riders in Dream KR Brain

Kamen Rider Poseidon becomes a member of Mu and fighting Kamen Rider Brain in Brain's dream. Kamen Rider Drive Saga: Kamen Rider Brain

Kamen Rider Poseidon

HD KR Poseidon

Kamen Rider Poseidon

"Same, Kujira, Ookamiuo!"
―Transformation announcement[src]
  • Height: 204cm
  • Weight: 89kg
  • Punching Power: 3.5t
  • Kicking Power: 7t
  • Maximum Jump Height: 45m
  • Maximum Running Speed: 100m/6.1 sec.

Similar to OOO, possessed Michal puts three Core Medals on the Poseidon Driver, and transform into the evil Kamen Rider Poseidon. The chest design have an inverse triangular position, which are arranged in the order of the Same on the right, Kujira on the left, and Ookamiuo below the Same and Kujira, unlike OOO's straight and diagonal arrangement. Kamen Rider Poseidon is designed as the light blue Same Head, the dark blue Kujira Arms with a whale's head on right shoulder and whale's tail on the left shoulder, and the dark red Ookamiuo's legs. Kamen Rider Poseidon uses a crimson spear as weapon.

Kamen Rider Poseidon, is actually the Greeed inside Michal's body. The Greeed overtook Michal's body and arrived to the present. It has the ability to create Waste Yummy, like how Uva did. The Greeed split from Michal, after losing some Core Medals to Eiji and Ankh. He was able to form his own body by using Core Medals and Cell Medals, in the form of Kamen Rider Poseidon. Then, Poseidon has been defeated at the hands of Kamen Rider OOO Tajadol Combo's Providence Drop and Kamen Rider Aqua's Oceanic Break. However, Kamen Rider Poseidon's Core Medals are taken for Kannagi to transform into the Super Galaxy King. After Super Galaxy King's destruction, Poseidon's Core Medals fells into the Earth and as the location of the medals were unknown.


Behind the scenes


Poseidon was voiced by Kenji Hamada (浜田 賢二 Hamada Kenji). His suit actor was Jun Watanabe (渡辺 淳 Watanabe Jun). While possessing Michal Minato, while keeping his voice, he is portrayed by Atsushi Arai (荒井 敦史 Arai Atsushi).