Lyon Arkland is the CEO of ZAIA Enterprise U.S.A. and the main antagonist of Zero-One Others: Kamen Rider MetsubouJinrai who transforms into Kamen Rider Zaia. He aims to mass-produce Humagear soldiers to sell as weapons across the world, and kidnaps Jin as part of his plan.

History:
Lyon Arkland is the CEO of ZAIA Enterprise's U.S.A. branch and worked with a multitude of other technological companies to develop Satellite Ark. He was the developer of the satellite's A.I. and therefore, Arkland became the namesake of the Ark. Despite creating the A.I., it was eventually sabotaged by Gai Amatsu who inputted information on human malice, resulting in the Ark to unleash a robotic revolt against humanity.

Arkland was conducting a conference with the other ZAIA branch offices. He expressed dismay towards Gai Amatsu & Williamson Yotagaki's actions in their tenure with ZAIA Enterprise Japan and declared the Sold Humagear plan would be put into practice, much to voices of opposition. After the meeting ended, he was visited by Azu who offered him a Zero-One Driver, scouting him to become the Ark's successor. However he declines as he preps to his arrival in Japan.

Outside the hideout of MetsubouJinrai.net in the abandoned Daybreak Town, Arkland arrived with Sold9 & Sold20 to capture Jin, before being saved by Horobi. Using the ZAIA Thousandriver that he confiscated from Gai Amatsu, Arkland transforms into Kamen Rider Zaia. He fought Jin & Horobi and taunted them as he overwhelmed the duo. Arkland would succeed in defeating him, briefly damaging Horobi's leg and captured Jin.

Arriving in the ZAIA Japan building, Arkland reveals to Jin that he is Sold 0 and after his first destruction, Jin's body was reconstructed as the prototype of the Sold Project. He reveals the Sold Project to be mass-produced, military type Humagears with no consciousness. Arkland intends to use Jin as a connection manager to the Massbrain System.

When Horobi, Naki, & Ikazuchi arrive to rescue Jin after following his transmission, it turns out to be a trap and Arkland and his Solds fighting the MetsubouJinrai Kamen Riders. As the quartet were trapped into the Massbrain System with Jin, they generate the MetsubouJinrai Driver and use the Massbrain Zetsumerisekey to transform into Kamen Rider MetsubouJinrai, much to Arkland's joy.

Arkland revealed his true goal to establish MetsubouJinrai.net as an enemy to humanity and market weapons of justice to defeat them. Arkland stated that previous successors of the Ark were able to overcome their malice, concluding that unwavering justice will give birth to battle, rather than malicious intent. Although Azu protested with Arkland's goals, Arkland mockingly shoots Azu with his fingers, which seemingly resulted in her actually being shot until it was revealed that the Solds fired their pistols at the Ark's messenger.

During an A.I.M.S. press conference set up by Yua Yaiba, Arkland arrived to accuse MetsubouJinrai.net of attacking the ZAIA Enterprise building and accuses the military organization for employing Naki. Things weren't going well for Yua's objection when MetsubouJinrai publicly declared to attack the ZAIA Japan building, causing increased tensions with A.I.M.S. and the Japan's National Defense.

With MetsubouJinrai's intent to release all the Humagear, including Sold, the quartet decided to become Kamen Rider MetsubouJinrai once more and succeeded in releasing the Sold from the Massbrain System, much to Arkland's shock. Arkland would then be killed by Kamen Rider MetsubouJinrai, due to the Massbrain System overwhelming the quartet.

Personality:
Arkland is a self-righteous and cunning businessman who sought to profit off of "justice" by igniting chaos. He intends to use the Solds to be weapons of justice and instigate MetsubouJinrai.net as a treats to humanity that the Sold will exterminate. Unlike previous successors of the Ark, Arkland isn't consumed by feelings of grief and anguish, believing that unwavering justice can overcome malice.

Arkland is also shown to be quite arrogant. Despite being aware of Gai Amatsu and his actions, Arkland doesn't seem to recognize Gai. Although it could mean that he never have not psychically met him, it could also mean that he doesn't acknowledge Gai and purposefully dismissing him as irrelevant, despite confiscating his Driver.

Abilities:
-Multilingualism: Lyon can speak both Japanese and English fluently, as well as interpret other foreign languages as seen with his conference call with other foreign corporate officials from ZAIA Enterprise.

Etymology: Lyon's surname, Arkland, is a reference to the Ark, one of the main plot elements and the antagonist of the series. In the movie, it is explained that the Ark was named after Lyon.