Doktor G

Doktor G (ドクトルG) / Kani Laser (カニレーザー) is Destron's first general in a knight armor who originated from Germany and was given charge to oversee their operations in Japan. He is the leader of the Mechanical Army. He wields a battle axe, a short sword, and a knife. In the comics, his scorpion-shaped helmet could transform into a deadly scorpion, but this didn't happen on TV. Most of his monsters are cyborgs that are the same type as Destron Leader's cyborgs. Pronounced his enemy's name "Kamen Raaaaida V3!". After numerous failures, Doktor G summoned the spirits of his dead, evil warriors to transform him into Crab Laser for his final battle with Kamen Rider V3. Despite putting up a heroic battle, he was destroyed by V3's V3 Tailspin Return Kick.

V3
Doktor G arrived in Japan after he was contacted by Great Leader of Destron who gave him orders to oversee their operations and to defeat Kamen Rider V3, Shiro Kazami.

Doktor G was responsible for the resurrection of Shocker's key figures (Colonel Zol, Doctor Shinigami, Ambassador Hell, and General Black).

Endgame
After so many of his plans were thwarted by V3 and his laboratory was destroyed by a special Interpol group known as the "Destron hunters." He personally confronted the hunters and killed them all (except for Ken Sakuma who was saved by V3).

Doktor G set a trap for V3 as an act of redemption for his failure as a Destron Commander, he kidnapped Tōbei Tachibana and the members of the Kamen Rider Scouts to lure V3. Doktor G summoned the spirits of his dead, evil warriors to transform him into Crab Laser for his final battle with Kamen Rider V3. Despite putting up a heroic battle, he was destroyed by V3's V3 Tailspin Return Kick.

Decade (Super Hero Taisen)
This version of Doktor G (ドクトルG) is a knight armored general of the revived Dai-Shocker in Super Hero Taisen. He's the second in command of the organization, bellow only its Great Leader, and standing above the other Great Commanders recruited by it. He wields an axe in battle and is able to assume the form of the Inhumanoid KaniGani Beam (可児ガニビーム), the modernized/Narutaki version of Kani Laser.

He is the driving force behind recreating Dai-Shocker, reviving and recruiting past villains and placing Tsukasa Kadoya, Kamen Rider Decade, as leader for the express purpose of defeating Dai-Zangyack and its leader, Captain Marvelous, Gokai Red and also the leader of the Super Sentai team Kaizoku Sentai Gokaiger. His Kani Laser form was much stronger than the original, resisting against the combined forces of various Sentai members and Riders, including Kamen Rider V3 himself, who defeated his previous incarnation. In the end, he was defeated by the combined efforts of Kamen Rider Decade, Ryuki, Blade, and the Goseigers, who gave the three riders new Gosei Cards. However, after being defeated, his appearance changes to Narutaki, who tells Decade that his journey will continue and vanishes behind a dimensional wall.

In fact, this version of Doktor G is just another one of Narutaki's disguises, similar to the Colonel Zol guise that Narutaki used when he joined Super Shocker. Unlike that time though, here Narutaki showed abilities and powers not only similar, but significantly stronger than the original's.

Kamen Rider SD
Doktor G: A member of GranShocker. He was among the meeting with the Great Leader.

Appearance
He wore a knight armor and wielded a battle axe, a short sword, and a knife. He also wears a Scorpion-shaped helmet, possibly to show his allegiance to Destron. In the manga, his helmet could transform into a deadly scorpion.

Portrayal
In the original Kamen Rider V3, Doktor G was portrayed by Jōtarō Senba (千波 丈太郎). The Doktor G seen in Super Hero Taisen is played by Tatsuhito Okuda (奥田 達士), who portrays Narutaki in Kamen Rider Decade.

Trivia

 * After the return of Shocker generals Colonel Zol, Doctor Shinigami, Ambassador Hell, and General Black in various forms in recent years, Doktor G's appearance in Super Hero Taisen makes him the first of the Destron commanders to return in a recent crossover movie. It remains to be seen whether Baron Kiba, Archbishop Tsubasa and Marshal Yoroi will follow suit in a future movie, such as Super Hero Taisen Z.

Appearances

 * Kamen Rider V3 episode 13 - Terrifying Commandant: Doktor G!!
 * Kamen Rider V3 episode 14 - Secret Memento of the Double Riders
 * Kamen Rider V3 episode 15 - Rider V3's Deadly Weakness!!
 * Kamen Rider V3 episode 16 - The Missile-Carrying Gecko Mutant!
 * Kamen Rider V3 episode 17 - The Devilspray is the Reaper's Weapon
 * Kamen Rider V3 episode 18 - V3, Beware the Evil Traitor!
 * Kamen Rider V3 episode 19 - Blowfish-Apache's Operation: Torpedo!!
 * Kamen Rider V3 episode 20 - Operation: Destron Shikoku Conquest
 * Kamen Rider V3 episode 21 - The Double Riders Live
 * Kamen Rider V3 episode 22 - Camp of Terror: Mystery of the Underground Canal
 * Kamen Rider V3 episode 23 - Terror! Vampire From the Graveyard
 * Kamen Rider V3 episode 24 - Mysterious! Cockroach Manor!!
 * Kamen Rider V3 episode 25 - Mysterious!! The Destron Ranger Corps
 * Kamen Rider V3 episode 26 - Mutant Heater-Cicada's Operation: Mummy!!
 * Kamen Rider V3 episode 27 - Zol, Death, Hell & Black Rise from the Grave
 * Kamen Rider V3 episode 28 - The Five Commandants' All-Out Attack!!
 * Kamen Rider V3 episode 29 - Doktor G's Final Challenge!
 * Kamen Rider V3 episode 30 - Doktor G! The True Form of Evil is...?
 * Kamen Rider × Super Sentai: Super Hero Taisen