Live action TV
Description
The character known as the Black Satan Great Leader serves as the central antagonist for the first half of the story and is the enigmatic head of the secret society Black Satan. This figure represents one of many incarnations of a recurring, immortal evil known as the Great Leader, who seeks to dominate the world through different organizations.

The true identity of the Black Satan Great Leader is intrinsically linked to the organization's primary tool of control, the Satan Bug. The Great Leader is not merely a user of these creatures but is in fact a gigantic, intelligent Satan Bug itself, acting as the original source and the collective hive mind that binds all other Satan Bugs together. This grotesque form is a massive, purple-bodied entity, standing approximately 200 centimeters tall and weighing around 113 kilograms. From its torso extend six long arms that resemble spider legs. At the center of its body is a face that resembles a human skull, which adds to its menacing and inhuman appearance.

In terms of personality and leadership style, the Great Leader is characterized by an absolute charisma that commands the fanatical loyalty of its followers. It maintains a strong, trusting relationship with its direct subordinates, such as the high-ranking officers Titan and Dead Lion. However, this trust did not extend to outsiders like General Shadow, a powerful mercenary brought in from another realm. The Great Leader was openly suspicious of General Shadow, viewing him as an untrustworthy foreign element, a distrust that ultimately contributed to a coup and the organization's downfall. The Great Leader rarely, if ever, left its hidden sanctum, an inner room that only the highest-ranking members holding a special artifact called the Satan Pendant could enter. To its lower-ranking soldiers and cyborgs, it remained a faceless, mythic presence, issuing orders through a voice emitted from a relief of its symbol.

The Great Leader's primary motivation is world conquest through the insidious spread of its Satan Bugs, which enter a victim's ear and take control of their brain, effectively turning them into a puppet of Black Satan. The Great Leader's main role in the story is as the hidden mastermind orchestrating Black Satan's campaign. For most of the narrative, it operates from the shadows while its generals, first Titan and later General Shadow and Dead Lion, clash directly with the hero. The Great Leader only steps into the spotlight after General Shadow initiates a coup and defects, sensing the rise of his own army. In a moment of crisis, the Great Leader chooses to abandon its compromised base. It is here, outside its hidden room, that it is finally confronted by Kamen Rider Stronger.

The character sees little development, serving as a static force of evil. Its key relationships define its actions. Its bond with Titan is so strong that after Titan is destroyed in battle, the Great Leader uses a dark ritual to revive him as the more powerful Hundred-Eyed Titan. In stark contrast, its relationship with General Shadow is one of mutual distrust, and it is General Shadow's betrayal that directly leads to the Great Leader's exposure. The Great Leader finally meets its end at the hands of Kamen Rider Stronger. Despite its powerful abilities, which include generating illusions to disorient opponents, teleporting instantly to escape danger, and possessing neurotoxins in its limbs, it is ultimately outmaneuvered. Stronger predicts the location of its teleportation and destroys it with a powerful combination of an Electro Punch followed by his signature Stronger Electro Kick. The explosion that follows signals the complete collapse of the Black Satan organization.