The former Kitchen Irish guard dog first appeared in Daredevil season 2, where he was adopted by Castle after his massacre of the Burren Club. Max was later kidnapped by the Kitchen Irish and threatened with torture to extract information from a restrained Castle.
After threatening his dog with a power drill, the Kitchen Irish get their answers from a complying Frank, taking the dog away — the last audiences see of him.
Castle and Daredevil dismantled the Kitchen Irish in a massive melee, and Castle was arrested in a cemetery soon after.
"I really am sad about that, man. That sucked," Bernthal said.
"He was a cool dog, too. He was supposed to come back at the end of that episode, when the police are coming. They couldn't get the dog to sit still, they just couldn't get the dog to do it, and they let the dog go," Bernthal explained. "I thought it was such a big mistake, I miss seeing that dog. Yeah, it sucked."
Max never showed up in Castle's subsequent solo series, The Punisher, meaning the dog was either killed in the ensuing chaos or — the better option — escaped and was taken in by a nice family, and lives in a home with a spacious backyard where he'll never again be used as a bargaining chip in a torture situation.
Bernthal also fielded questions about his Marvel Cinematic Universe co-stars, singling out Spider-Man actor Tom Holland with high praise, and naming which members of The Defenders he'd like to team up with next.
ACE Comic Con also featured appearances from Captain America: Civil War and Avengers: Infinity War stars Chris Evans, Anthony Mackie and Sebastian Stan, who opened up about their time on Marvel Studios' massive blockbuster sets.
Bernthal will return for The Punisher season 2, officially announced by Netflix in December.
All episodes of The Punisher are available for streaming exclusively on Netflix.