In Kumamoto,Japan (1893 AD), Ichisumi's powers first awoke. She suffered from a severe inferiority complex. Perhaps brought on by her abusive father, a proud samurai who was mad at her repeated failures. As a geisha she was also jealous of the more beautiful and intelligent geisha around her who were more successful. Fueled by her repressed rage and the disapproval of her father, she wished to disfigure the other geishas and Ichisumi's power first manifested, she let loose a swarm of "yume"* beetles that instead ravaged all the women in her village and hundreds of others. The beetles also absorbed the memories of the massacred women. Ozymandias mentions that the memories drove her insane. Impressed with her abilities Apocalypse directed Ozymandias to add her to his cadre of Final Horsemen, appointing her Pestilence.
Hundreds of years later, Pestilence and the other final horsemen, fight the new X-Force in their base on the moon. They easily defeat the team.
Pestilence was created by Rick Remender and artist Jerome Opena and first appeared in Uncanny X-Force Vol.1 issue 2 (2010).
Major Story Arcs
She fights against Fantomex, unleashing a swarm of beetles, however Fantomex uses misdirection and shows Ichisumi's father. Ichisumi tells her "father" that she has become a proud warrior but her father says she's a disappointment because she's nothing more than a pawn. Removing the illusion, Fantomex knocks her out.
Later when Wolverine stabs Death , Death mocks Wolverine and bombards him with all of mankind's illnesses ( Death's power is to transmit sicknesses through metal objects and Wolverine has not only metal claws, but his entire skeleton is laced as well). As he prepares to "finish" Wolverine, Ichisumi appears in Death's hands, covered with a number of the diseases he thought he was killing Wolverine with. With the illusion disbersing, Fantomex and Wolverine hide in order to recover. Pestilence and the Horsemen ultimately fail as X-Force reach the child and kill him.
Dark Angel Saga
When X-Force return from the Age of Apocalypse and their search for a cure for Archangel, they find he has enlisted the aide of Pestilence and the Horsemen in his evil plot. It is revealed that Pestilence is carrying the unborn child of Archangel as she escapes with Dark Beast at the end of the Dark Angel Saga.
Ichisumi's jaw detaches to send forth a massive legion of "yume beetles". The yume beetle swarm may be psionic in some quality because they absorbed the memories of its victims. Also, yume* roughly translates to dream in Japanese.