Impactor Lucia is a fictional character from the Japanese television series Chōseishin GranSazer. She is a member of the Impactors, an alien race that arrives on Earth as part of a larger mission. Lucia is a swift and cunning fighter who typically assumes the appearance of a human woman in her twenties, characterized by a distinctive red streak in her hair. In this form, she is often seen wearing a green leotard and a cape. When engaging in combat, she adopts a black-armored battle form.

Lucia is driven by a deep and unwavering love for her superior, Logia. Her loyalty to him is a central aspect of her personality, and she is willing to do anything to earn his approval or act on his behalf. This devotion often puts her at odds with other members of her team, particularly Radia, who harbors feelings for Lucia, creating a subtle romantic tension within the Impactor ranks. Her determination to prove herself and follow her emotions, rather than strict orders, is a defining trait.

In the story, Lucia comes to Earth alongside Radia to participate in the conflict against the Gransazers, the series' protagonists. After Radia is killed, Lucia is consumed by a desire for revenge, swearing to destroy the Gransazers even when Logia orders her not to act. This disobedience leads her into direct confrontations with several of the Gransazers. During one such battle, she is scarred by a Gransazer named Ai, which fuels her vendetta further and leads to a subsequent fight where she is mortally wounded.

Lucia is taken to a hospital, but her alien body is beyond the help of human medicine. Facing death, she is saved when Logia intervenes and heals her, revealing that he reciprocates her feelings. After recovering, she is told she can no longer continue her mission. Unable to accept this and still driven by a desire to succeed, she defies orders and uses a forbidden device called an Accelerator to increase her power. This allows her to grow to giant size, but it comes at a great cost, as the Accelerator will eventually rob her of her sanity and lead to her death. In this amplified state, she overpowers the heroes' super robots with abilities like cloaking and creating clones, but she is ultimately defeated by the combined might of the Chouseishin. As the Accelerator's fatal effects take hold, Lucia succumbs to her injuries and dies, leaving behind a card for Logia to find as a final memento.

As a fighter, Lucia is highly skilled and, in her standard armored state, is more than a match for a single Gransazer. Her primary weapon is the V-Sword, a bladed weapon that can be used in close combat or thrown like a boomerang. She can also generate a green beam called the Death Eraser from the sword's blade, fire electric shocks from her hands to paralyze enemies with the Stun Impulse, and create a circular barrier known as the Impact Wall for defense. One of her more advanced techniques is the Mirage Cluster, which uses a special Ark to create physical clones of herself to confuse opponents. When using the Accelerator to grow to giant size, she gains additional devastating attacks such as the Plasma Chopper, a widespread energy barrage, and the Megalo Cluster, which allows her to surround an enemy with multiple smaller copies of herself. She also gains the ability to become invisible for a stealth attack. Her final, desperate transformation allowed her to grow even larger than the Chouseishin, though at the complete loss of her self-control.