The Punisher is one of Marvel's most iconic anti-heroes, an unrepentant killer who brings war against the criminals of the world. He also notably has no patience for those who take his rage at life on a surface level and try to replicate his efforts, leading him to kill many of the Punisher imitators he's encountered over the years. But there's one that always seemed to genuinely get through to him.
Two of the most important characters to be inspired by the Punisher -- the Outlaw of Earth-616 and the Punisher of the Marvel 2099 timeline -- once got the chance to face off and prove which one was the rightful heir to Frank Castle's legacy.
Nigel Higgins -- aka Outlaw -- was introduced in Punisher #64 by Dan Abnett, Andy Lanning and Douglas Braithwaite. Higgins was an admirer of Frank Castle and his war against crime. Inspired by him, he became the Punisher of England -- even working with Castle and Microchip to combat Kingpin's attempts to spread his influence into Europe. He consistently proved to be a skilled ally of Frank's, even coming to America in search of Frank during his apparent death during the "Suicide Run" crossover. However, after faking his death and killing plenty of criminals, Higgins came to the realization that he didn't have it in him to kill anyone else, and tried to retire from active heroics.
Another person inspired by the actions of Frank Castle was Jake Gallows. Debuting in the pages of Punisher 2099 #1 by Pat Mills, Tony Skinner and Tom Morgan, Gallows was a police officer in the Marvel 2099 timeline. After his family was killed and the culprit received no severe punishment for his actions due to his connections and wealth, Gallows became inspired by the last of Frank Castle's War Journals to take up the mantle of the Punisher. He became a brutal vigilante of the era and utilized a number of deadly weapons in his crusade, and became one of the most prominent characters in the 2099 line alongside the Spider-Man and Doctor Doom of this era.
The two got the chance to meet in the aftermath of Secret Wars in Contest of Champions by Al Ewing and Pac Medina. Following the multiversal conflict, the Elders of the Universe found the remains of Battleworld and turned it into a tournament -- with the Grandmaster choosing Jake Gallows as his champion. Gallows quickly proved a capable warrior, making it to the final round and finding himself pitted against a variant of the Maestro (a dark older incarnation of the Hulk who'd become twisted and villainous in his later years). The pair refused to fight and instead offered their services as new summoners for the continued contest, secretly planning to take the Iso-8 for themselves.
Among those chosen was the Nigel Higgins of Earth-616. Gallows revealed a particular dislike for the former vigilante, considering him someone who'd given up on the legacy of Frank Castle. When the captured champions were given the chance to escape, Gallows found them and challenged Higgins to a face-off -- although it was quickly interrupted by Higgins instead just knocking out Gallows. The two were given one more chance to face-off, this time with the intervention of a Frank Castle from a reality where Iron Man won the superhuman Civil War with the help of the Infinity Stones.
This Punisher had also known Outlaw and approved of his crusade. But when he learns how Outlaw gave it up because he couldn't go on believing murder was alright, Frank seems to accept his reasoning and allowed him to live. On the other hand, Gallows' arrival on the battlefield leads him to vow to bring vengeance to Maestro for the sheer sake of it -- prompting Castle to put a bullet in his forehead because he didn't approve of Gallows. It's a brutal reminder that to the Punisher, there needs to be cause and purpose to murder, regardless of who you're targeting. Otherwise, someone is no better than all the criminals he's put in the ground. In the end, Outlaw was the only true inheritor of the Punisher role -- and proved himself the better man by being able to give it up in a way Frank never really can.