Hayden Katsumi

Hayden Katsumi is Kamen Rider Eternal, the main antagonist in Kamen Rider Double Detective Forever: A to Z/The Gaia Drives of Fate and before the Summer Film, he was the main protagonist in Kamen Rider Double Detective Returns: Eternal.

Early Life
Hayden was the leader of the organization NEVER that uses the T2 Gaia Drives. He lead the NEVER Dopants created from the T2 Gaia Memories to attack Futo City.

In The Beginning of N/Blood and Dream, it is revealed that Hayden was born with a congenital heart defect. This, combined with a fatal car accident, prompted his mother, Maria Katsumi, to use her NECRO-OVER project research, based on Charlie, to save her son's life as the first Necro-Over, giving him bio-stimulants to age properly. However, despite Hayden proving to be a skilled fighter (especially with combat knives), the Necro-Over project was rejected in favor of the Gaia Drives project, so Hayden and his mother left the Foundation. Transforming four people who recently died into Necro-Overs, they founded NEVER. Katsumi is more refined and enhanced than the other Necro-Overs.

Attack on Futo
Hayden and the other members of NEVER were fighting a terrorist organization in South Asia, where he encountered a Quark named Mina and fell in love with her. After a brief meeting with Professor Kazu, gained the experimental Eternal Drives to become Kamen Rider Eternal. But when Doctor Prospect as the Eyes Dopant killed all of the Quarks, supposedly even Mina, Hayden went mad and killed Prospect with Drive's Maximum Drive. With the Eternal Drives damaged, Hayden discarded it and decided to wipe out the Museum.

In the film, Hayden first appeared attacking the helicopter Tabata is riding in, taking the T2 Eternal Drives and transforming into Eternal. He takes the entire case containing the T2 Gaia Drives and goes to his accomplices. But Tabata activates a switch causing the case and helicopter to explode, scattering the Drives. However, Hayden survives, and he and his comrades search for the remaining Drives.

Hayden then appears at the place the Riders of Futo came to meet Maria Katsumi, where he fights Kamen Rider Double Detective as both FangJoker and CycloneJokerXtreme and easily overpowers both forms. He shuts down access to the pre-T2 Gaia Drives, saying that he and Charlie are a lot alike, which only makes Charlie more livid. After Double Detective is defeated, NEVER claims the 19 T2 Gaia Drives that the Riders found.

With 25 of the 26 T2 Gaia Drives recovered and Charlie captured by NEVER, Hayden reveals his plan to take over and rebuild Futo City in his image, with the people turned into Necro-Overs. Reclaiming the T2 Joker Drive from Charlie's partner, Simon Holmes, Daido initiates the X-Bicker that will send out a wave to turn everyone into Necro-Overs, despite knowing that they will die as they are not enhanced as Hayden is. Charlie, with help from Simon, reactivates their Gaia Drives, and Maria injects a serum into Katsumi that causes him to start dissolving. In retaliation, Katsumi shoots Maria in the stomach and takes another serum to stabilize himself which seemed to weaken him.

They manages to catch up to Hayden as he transforms into Eternal, but the latter escapes again. Double Detective then catches up and fights Eternal on the Futo Tower using his Half Forms. As he is about to deliver the final blow as CycloneJokerXtreme, Eternal seemed to regain his full strength and goes into his Strengthening Armament mode, using the Zone Drive to summon the other T2 Gaia Drives. He then uses the 'Never Ending Hell Maximum Drive to send Double Detective falling from Futo Tower to his death, but through the support of the citizens of Futo and a strong gust of wind blowing into the Xtreme Drive, Double Detective changes from CycloneJokerXtreme to CycloneJokerGoldXtreme. Eternal then uses his energy to send one blast of energy at Double Detective, but Double Detective counters through the attack and hits Eternal with a kick strong enough to defeat him as well as destroy all 26 T2 Gaia Drives at once. With his very last breath, Hayden remembers what death feels like.

Red Flare
Ability Perimeters: Red Flare is Eternal's weaker/incomplete form. This form of Eternal was accessed by Professor Kazu using the standard Eternal Drive, but due to incompatibility with the memory, he could only access the Red Flare form. Unlike it's Blue Flare counterpart, it lacks the extra Drive Slots, and Eternal Robe, and the flame designs on the arms and leg bands are red instead of blue, true to this form's name. In W Returns, Katsumi briefly transforms into Red Flare before evolving into Blue Flare after stealing the drive and the Lost Driver from Professor Kazu.
 * Height: 205 cm.
 * Weight: 95 kg.
 * Punching Power: ??
 * Kicking Power: ??
 * Maximum Jump Height: ??
 * Maximum Running Speed: ??



Normal
Ability Perimeters: Through the Lost Driver and the T2 Eternal Drive, Katsumi transforms into Kamen Rider Eternal. Eternal's Maximum Drive with the Eternal Edge is the Eternal Requiem, a power wave that cancels out all other Gaia Drives. Like most Riders in Kamen Rider: Double Detective, Eternal has an English letter motif, in this case the letter E.
 * Height: 205 cm.
 * Weight: 95 kg.
 * Punching Power: 7 tons
 * Kicking Power: 12 tons
 * Maximum Jump Height: 150 m
 * Maximum Running Speed: 100 m. per 3 sec

Eternal is also adorned with a black Eternal Robe cape after transformation. His catchphrase is "Now, enjoy Hell". Eternal's mask slightly resembles a horned owl and an infinity symbol. His primary Motifs are the letter E and a military commando.

In this mode, he is able to execute the Eternal Reqieum Maximum Drive utilizing the Eternal Edge. In addition to the Maximum Slots on the Lost Driver and the Eternal Edge, Eternal Blue Flare has a series of Maximum Slots on belts around his chest, right arm, and left leg, for a total of 26 for every T2 Gaia Drives.

This form is called Eternal's Blue Flare} form, as revealed in Kamen Rider Double Detective Returns]], which is more powerful than the incomplete Red Flare form.



Strengthening Armament
Ability Perimeters: By filling all 26 of his Drive Slots through the T2 Zone Drive, Eternal enters his Strengthening Armament mode.
 * Height: 205 cm.
 * Weight: 97 kg.
 * Punching Power: ??
 * Kicking Power: ??
 * Maximum Jump Height: ??
 * Maximum Running Speed: ??

In this mode, he is able to absorb the X-Bicker's energy to produce the Eternal Wave to execute the Never Ending Hell Maximum Drive utilizing the Eternal Edge.

However, the Strengthening Armament is only usable in Blue Flare form.



Equipment

 * Lost Driver - Transformation belt, stolen from Jun Kazu.
 * Gaia Drives - Eternal's USB-like devices that enables him in his transformation or powering his attacks. Wields only one, Eternal Drive and destroyed after it's use.
 * T2 Gaia Drive - Next generations of Gaia Drives made by Foundation X
 * Eternal Edge - Dagger/combat knife utilized by Eternal for combats