Hideyasu Jonouchi

Hideyasu Jonouchi (城乃內 秀保) is Kamen Rider Gridon (仮面ライダーグリドン), the scheming leader of Team Invitto and the fifth Rider in Kamen Rider Gaim. He uses the Donguri Lockseed.

It is revealed that Ryoji was the one who had named Hideyasu's Armored Rider as Gridon, but Hideyasu himself dislikes the name.

Character History
Before Ryoji battles Team Gaim, Hideyasu warns him that he couldn't win against Team Gaim.

Alliance with Team Baron
Sometime later, Kaito forms an alliance with Teams Raid Wild and Invitto as he gives them Lockseeds to win against Gaim. After Team Gaim finish dancing, Hideyasu appears as he battles the team with the Ichigo Lockseed Kaito gave him; however Mitsuzane got his own Sengoku Driver as he transformed into Armored Rider Ryugen and ended up being defeated by the new rider.

Gaining a new power
After he loses his Lockseed to Armored Rider Ryugen, Hideyasu goes to Kaito's place for a new Lockseed. As he gains a Lockseed from him, Kaito started to mock him as he is weak, which made Hideyasu curious about the alliance. After getting a Donguri Lockseed from Kaito, he then went to Drupers and finally understands what Ryoji says before telling him how foolish they were in allying with Baron, thus telling him that they will be Baron's slaves. Refusing to let that happen, they would have a chance to be on the same level as Kaito, and thus gaining Sid's attention as they received Sengoku Drivers from him. After Baron's Inves are defeated, he and Ryoji appear as they transform into Armored Rider Gridon and Kurokage respectively, which surprises Team Gaim.

First fight and confrontation with Bravo
"I am Armored Rider Kurokage" "Eh, we are naming ourselves? Then I am..." "Oh, this is Armored Rider Gridon" "What !?"

- Kurokage naming Gridon much to Team Gaim's laughter

After they transform, they easily beat up Baron, but Team Gaim's Armored Riders finish them off, also gaining their Lockseeds. Sometime later, Hideyasu and Ryoji buy replacement Lockseeds as he notices one member of Red Hot got a Sengoku Driver and a Lockseed from Sid. Later, Kurokage and Gridon were doing some training until some people arrive, thinking that there will be a battle. Oren then reveals that he announced the battle as he transforms into Armored Rider Bravo to fight Gridon and Kurokage. However, Gridon was later easily defeated by Bravo.

Personality
Hideyasu is a calm-looking person and is a brilliant tactician, forming strategies of attack when the best means of winning are not available. This is shown when he attacks Team Gaim when Kota is not around and suggesting he and Ryoji get their own Sengoku Drivers. Despite his confidence in strategy, he has no actual combat skills after becoming an Armored Rider due to his inexperience. This is proven during his battles against Ryugen and Bravo when he became a human shield for Kurokage. He is also a coward, hiding as Kurokage was being beaten by Bravo and prefering sneaky tactics. He is not very confident about going against gun-slinger Armored Rider, like Ryugen and prefers to hide from gunfire.

Arms
As with the other Kamen Riders that uses Lockseeds, Kamen Rider Gridon's forms are called Arms (アームズ).

Devices

 * Sengoku Driver - Transformation device
 * Lockseed-exclusive weapons:
 * Donkachi - Gridon Donguri Arms' personal weapon
 * Lockseeds - Gives access to Gridon's form changes, depending on which arm the lock is

Vehicles

 * Dandeliner - Kamen Rider Gridon's Rider Machine
 * Rose Attacker - Kamen Rider Gridon's second Rider Machine

List of Appearances

 * Kamen Rider Gaim
 * 3-7,'' 10
 * Kamen Rider × Kamen Rider Gaim & Wizard: The Fateful Sengoku Movie Battle
 * Kamen Rider Gaim: Sengoku Movie Battle

Portrayal
Hideyasu Jonouchi is portrayed by Ryō Matsuda (松田 凌).

As Kamen Rider Gridon, his suit actor is Kazuya Okada (岡田 和也), who was previously the suit actor for Gremlin in Kamen Rider Wizard.