Hajime Shijo

Hajime Shijo (四条 ハジメ) is the president of the BOARD Corporation who secretly uses the sealed Mantis Undead to assume the form of the legendary Kamen Rider Chalice. Because he is more interested in business ethnics, Hajime sees himself as the only thing keeping BOARD alive by offering his company's aid once paid by the government.

Furthermore, he conspires with Kamata by taking the other Rider Systems to begin a joint plan to take over the world by creating the Joker card from the DNA of all four Ace Undead. Being unable to get Kazuma to give him the Blay Buckle by normal means, Chalice makes his presence known during Decade and Blade's fights against the Paradoxa Undead and the other BOARD Riders, stripping Kazuma of his Blay Buckle before fighting Decade until Todoroki's sudden appearance.

But Hajime escapes with the Garren Buckle as well, later taking the Leangle Buckle with his identity exposed to Hishigata and Mutsuki whom he abducts and sacrifices to complete the Joker card. Assuming the form of the Joker, Hajime meets his end at the hands of Blade and Decade.

Super Hero Taisen
A Joker Undead is present as one of the Kaijin Generals of Dai-Shocker in Super Hero Taisen. Given the fact that Hajime Aikawa was one of the Support Riders that Kamen Rider Birth brought in Let's Go Kamen Riders, it is safe to assume that this Joker is Shijo.

Chalice Rouzer
The Chalice Rouzer (カリスラウザー) is a Rider System created for Shijo himself. The full extent of its power is unknown, but the Chalice Rouzer is capable of reproducing the DNA of sealed Undead and mimic their forms with frightening accuracy, as well as their respective powers and abilities. Further adding to its uniqueness, is that Rouze Cards are swiped on it, which became the template for the Rider System's Rouzer technology.

This Rouzer can be removed from the belt and used as a "brass knuckle" sort of weapon to enhance punches or inserted into the Chalice Arrow to use it to scan Rouze Cards without transforming into the Undead.

Chalice Arrow
The Chalice Arrow (カリスアロー) is Chalice's weapon and Rouzer, and functions as a multipurpose weapon. Simply put, it is composed of a bow with its curved ends as sharp as blades. This weapon is capable of shooting projectiles, as well as engage opponents up close using the bladed ends of the bow. The bow can also fold up, turning the Rouzer into a brass knuckle for stronger punches. By inserting the Chalice Rouzer into the bow, the Arrow can serve as the Rouzer for Chalice, activating Rouze cards without turning Chalice into an Undead.

Portrayal
Hajime Shijo is portrayed by Ruo.