The PX-Series of cyborgs are characters from the One Piece series, created by Eiichiro Oda. The series first began serialization in Weekly Shōnen Jump on August 4, 1997. They did not appear until the Sabaody Archipelago arc.
They first appeared in One Piece Volume 52 CH. 505"Kuma", and their first anime appearance was inOne Piece - Episode 399, "Break Through the Encirclement! Marines vs. Three Captains". wasn't revealed just how many there were until One Piece - Episode 470"The Great Swordsman Mihawk! Luffy Comes Under the Attack of the Black Sword!". This was also their grand debut to the entire world. In the Japanese series they are voiced by Hideyuki Hori, the same voice actor of Bartholomew Kuma.
PX-4 defeated by the Straw Hat Pirates
These cyborgs are exact copies of the Shichibukai member Bartholomew Kuma. He had consented to undergo transformation into a cyborg by Dr. Vegapunk. They are not exact copies and the idea that they were merely machines was proven wrong when they were shown to bleed red blood when injured enough. Since these PX cyborgs are copies, they do not have his Paw-Paw Devil Fruit powers. The real Bartholomew Kuma can be identified by the bible he carries everywhere and the paw prints on each palm. They speak very little, and only to announce the names of the bounties they spot.
Even if they are copies, the durability of the PX Series is nearly on par with the original Bartholomew Kuma. It is unknown how Dr. Vega Punk created so many copies of a human being, but these seem to lack all sense of self awareness and only follow the orders they are given. It's also unknown just how many exist in the world. After the final step, Bartholomew Kuma made a full transition he was declared as dead and became PX-0. Though he was believed that Kuma's personality was dead. He has taken mysterious actions on his own.
Major Story Arcs
Sabaody Archipelago Arc
Fish-Man Island Arc
Powers and Abilities
In place of the Paw-Paw powers of Kuma, in the hand of each of the PX Series is a laser cannon that is similar to the laser beam of Marine Adrmial Kizaru. They also have a laser cannon built into their mouth. This is also found on the original Kuma. They are normally seen under the command of Sentomaru.