Shortly after a tour in Vietnam, Castle, his wife, Maria and their children were in New York's Central Park for an afternoon picnic when they witnessed a Mafia gangland execution; an informant had been hanged from a tree. Seeking to eliminate all witnesses, the Costa crime family murdered them on the spot. However, Castle survived. Even though Frank was able to identify all of the shooters the police were unable to help Castle in his quest for justice; they were tied in too deeply to the powerful Costa family. He decided that the only punishment criminals might receive is that of physical destruction. Shortly thereafter, he emblazoned his body armor with a symbol of a death's head, and exacted his revenge. Since then he has waged a one-man war upon crime, taking the name Punisher.In his vigilante endeavors, Castle has crossed paths with several costumed crime-fighters, most notably Spider-Man and Daredevil. These encounters have often resulted in his incarceration. While he is known to be significantly inferior to Daredevil in hand-to-hand combat skills, Punisher has been rated as one of the most dangerous criminals alive. When he was incarcerated in New York's Riker's Island Prison, though heavily outnumbered in gang-fights, Punisher has routinely killed armed, homicidal criminals with frightening ease, sustaining no injury. Due to his proficiency in fighting, he is rarely so accosted in prison environments. Adhering to his military philosophies, Punisher is constantly training whenever he is not out on actual maneuvers. He exercises fanatically to maintain his impressive physical conditioning and sticks to a balanced diet whenever possible.
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