Francis "Frank" David Castle Sr., also known as the Punisher, is a supporting anti-protagonist in the Kingdom Hearts Unlimited Saga, first appearing in "Encoded Truths" as a rival in the Hell's Kitchen campaign.
Frank is a rather brutal vigilante who, after the brutal murder of his entire family, aims to clean up New York City of crime by any means necessary. While searching for all those responsible for his family's death, Castle came into conflict with the blind hero Daredevil, who felt Castle's methods were too extreme. After several encounters, Castle was soon arrested for his crimes and, despite the efforts of a sympathetic law firm, was sentenced to life in prison. However, Castle was freed with the help of Wilson Fisk, alias the Kingpin, and soon discovered his former commanding officer in the Marines, Ray Schoonover, was the one responsible for his family's murder all just to cover up his illicit activities as the crime lord known as the Blacksmith. After exacting his rightfully-earned vengeance on Schoonover, Castle reluctantly helped Daredevil defeat the forces of the Hand, and then proceeded to move on from his own past, now dedicating his life to permanently punishing criminals wherever he found them, aiming to make the city a better place.
(cited from the MCU wiki article)