IV

{{nihongo|I-V|is the human alter-ego of {{nihongo|Cyber Rider G4|Masked Rider G4}}, a Rider who only appeared in ''Taisen 2008".

Overview
He was one of the military personnel guarding the GA psychic educational facility during the time it was attacked by the Form Dece. Though he would survive the ordeal, he would be left a jaded man.

With his pride as a soldier shattered, Mizuki began living as one who would embrace death as the true means of becoming stronger. He would eventually volunteer as the operator for the G4 exo-suit and, as fate would have it, clash with G3-X operator Trio], to put their ideals to the test on the battlefield. But throughout the course of the battle, the G4 begins to suffer malfunctions.

But despite this, Troy refused to surrender. In the end, Troy would succumb to the strain placed upon him by the G4 and die. The G4's AI attempted to rise and continue the battle, but was destroyed by Trio and Drake Ridley.

Decade

 * G4 Chip appears in Kamen Rider DCD series. The chip was found in Drake Ridley's old locker by Asthon Seymour. The chip, however, was destroyed by Toko Yashiro.
 * In Kamen Rider × Kamen Rider W & DCD: , G4's Gigant was used by DCD, through "Attack Ride: Gigant" card which means G4 may be carded by Decade.
 * G4 makes another appearance in Kamen Rider × Kamen Rider × Kamen Rider The Movie: Cho Electric King Trilogy Episode Yellow: Treasure de End Pirates, he was summon by Kamen Rider Diend Complete Form with "Movie Verison" Attack Ride Card alongside with other 7 Riders: Onyx, Omega, A-Jack, Kabuki, Kamen Rider Atlurborg, Kamen Rider Colossus, and Skull Rider.

Masked Rider of Mystica video game
In the Mystica (video game)|Kamen Rider Agito gamefor the Playstation, while G3/G3-X has limited fighting time and will instantly K.O after the time is over, G4 doesn't suffer that limitation, possibly because G4 is a more advanced version and has successfully eliminated the weakness of G3/G3-X system.

Kamen Rider Battle War II
G4 reappeared in Kamen Rider: Battle War II.

Cyber Rider G4


Cyber Rider G4 was an upgraded version of the G3 system conceptualized by Summer from the G3-X model. However, the G4 was deemed far too dangerous for use, so Summer never included the adjustments in the design schematics. But, Risako Fukami would steal the plans and construct the G4 System herself, adding a Prediction System to improve the AI and make the G4 the most powerful weapon on Earth. Unlike earlier G-Series of Kamen Riders motif based on Kuuga, G4's motif was based on Kamen Rider Agito.
 * Head height: 198 centimeters (6ft 4in)
 * Base weight: 150 kilograms (330.6lbs)
 * Ability perimeters
 * Punching power: 4t
 * Kicking power: 13t
 * Maximum jump height: 25m (82ft)
 * Maximum running speed: 100m/7.5s (328ft/3.5sec)
 * Vision: 15 km approx. (9.3 miles)
 * Hearing: 15 km approx. (9.3 miles)
 * Defense Rating: 8

Physically, G4 would reflect Agito's Burning Form, but the horns on G4's helmet resemble Agito's crest horns (unopened) from his basic Ground Form. The rest of the armor re-uses the design of the G3-X design, save for the shoulders which are held over from the original G3 design.

Equipment

 * GM-01 R4 - A modified version of the Kamen Rider G3's GM-01 "Scorpion"; a modular magnum pistol, stored on right hip, hand-carried in use.
 * Gigant - A shoulder-mounted missile launcher, mounted over the right shoulder when in use. Used as a finisher.

Rider Cards

 * Kamen Ride: G4: A Rider Card containing the power of Cyber Rider G4, possessed by Kamen Rider Diend. It one of the eight cards used by Diend Complete Form. It summons Cyber Rider G4.
 * Attack Ride: Gigant: The Gigant Attack Ride Card is used by DCD to summon Cyber Rider G4's Gigant to attack enemies. Used to defeat Masked Rider Super G2.

Rider notes

 * In terms of the users (Trio and I-V), the utilization of the G3-X and the G4 exo-suit near the end of 2008 Taisen is reminiscent of the final battle between Masked Rider Ultimate Form and Lord Stagger.
 * I-Vand N-Daguva-Zeba also happen to be more willing to die (and end up doing so) for their motives, with Mizuki fighting for his ideals in life, and N-Daguva-Zeba fighting to accomplish either one of his goals.
 * Unlike the majority of American Dark Riders who are based on the Primary Rider in their respective series, G4 is the first one based on the Secondary Rider.
 * Though, by extension, this also means he's based on the Primary Rider from the previous season.