Pestilence (Supergirl)

"My mother used to always say that good will be rewarded with grace. But when I became a surgeon, I finally saw the truth. There is no reward for being good."

- Grace declaring her view of being "good". "Stop it. Why would I ever want to stop it? This is the greatest thing that's ever happened to me. I don't have to worry about saving anyone because I don't want to. I get to choose who dies. They say that surgeons have a god complex, but it's simple: I am a god!"

- Grace showing Supergirl her true colors. Grace Parker, also known as the Worldkiller Pestilence, is one of the two secondary antagonists (alongside Purity) in Season 3 of the TV series, Supergirl.

Alongside her "sisters", Reign and Purity, Pestilence was sent to Earth upon Krypton's destruction and was then raised under the name "Grace Parker". After many years, her powers were awoken. However, unlike her sisters, it is shown that she has somewhat embraced her alter-ego. According to Imra Ardeen, her powers of inducing sickness would evolve in the future and she would become an entity known as the Blight and would slowly wipe out nearly all life in universe in the 31st century.

She is portrayed by Angela Zhou.

Biography
Pestilence was born on Krypton with a bio-genetically modified physiology, like Reign and Purity. Upon the planet's destruction, Purity, along with the other Worldkillers were sent to Earth. Upon arriving, she was adopted and raised as "Grace Parker". Her mother used to tell her that being good would be rewarded with grace. However, after becoming a surgeon, she came to a realization that there was no reward for being good, thus losing her utter faith in life.

After Reign had awoken, Grace's powers began to manifest along with her alter-ego. However, unlike her sisters, Grace had embraced her alternate personality and decided to use her powers to judge who lives and who dies. This development gained her a god complex as she had control over life and death. She took action by starting to infect birds, which then fell from the sky, unintentionally catching Supergirl's attention.

Grace then started targeting and infecting businessmen that she viewed as greedy and self-centered. After infecting these people, she later appeared at the scene as a strict doctor. Upon meeting Winn Schott and Alex Danvers, she touched them, secretly infecting them while also framing someone else whom she also infected.

Later, she arrived at a corporate meeting and planned to infect and kill them. However, Supergirl arrived and stopped her. Supergirl then tried to reason with her, believing that her Pestilence personality is controlling her, only for Grace to show her true colors and then engages in a fight with her, Mon-El and Imra Ardeen. Although she was beginning to win, Imra gained an upper hand and attempted to poison and kill her to alter her future as Blight. However, Purity arrived and overpowered the three before escaping with Grace to help her fully embrace her Pestilence side.

Later, she and Purity arrived to save their leader Reign, who was being held in a secret facility by Lena Luthor, therefore uniting all three Worldkillers before taking off.

Possible Future
According to Mon-El, in the 31st century, Grace has evolved and became the Blight who killed many people on Earth, including Imra's sister. The Legion was sent to the present to prevent her evolution.

Powers and Abilities
Due to her origins as a Kryptonian, Purity does share similar powers to Reign, Supergirl and Superman, including super strength, flight and invulnerability. However, unlike other Kryptonians, due to being bio-genetically modified as a Worldkiller, she appears to have different abilities as well, which notably includes her power to induce pestilence against her enemies upon direct contact, as demonstrated when she infected Winn Schott and Alex Danvers after simply touching them. According to Imra Ardeen, her power evolves and become more contagious which results in the infection and apocalyptic deaths across the universe in the 31st century. Considering that her powers have continued to destroy species in the future, she may also possibly have extended longevity, being able to live beyond a lifetime. Thanks to her altered physiology, she can go toe-to-toe with Supergirl, Imra Ardeen and Mon-El in one fight.

Trivia

 * Despite being the third and final Worldkiller introduced, regarding her powers, her god complex and her supposed future, Pestilence is possibly the most dangerous Worldkiller there is, even outranking Reign.
 * Like Purity, Pestilence is an original character. However, her future code name, Blight, is an allusion to a DC Comics nomadic race of techno-organic beings, who assimilate new races in search of immortality, but turning everyone into perpetually decaying techno-zombies in the process.