Attendees dressed as Poison Ivy and Harley Quinn arrive for opening day of the annual Comic-Con International in San Diego, California, United States July 21, 2016. (Photo by Mike Blake/Reuters)

Jason Garcia poses as The Joker from Batman at the 2015 Comic-Con International in San Diego, California, July 9, 2015. (Photo by Sandy Huffaker/Reuters)

The head of a decapitated rooster is pictured after a rooster run, during celebrations in honour of San Juan Bautista in San Juan de Oriente town, Nicaragua, June 26, 2015. The rooster runs, where horse-riders try to pull the head off live roosters, symbolize the beheading of John the Baptist. (Photo by Oswaldo Rivas/Reuters)

Convention goers dressed as bright colored Wookiees, a fictional species from the US epic space opera franchise Star Wars, prepare for a group photo outside the Comic Con 2016 in San Diego, California, USA, 22 July 2016. The San Diego Comic Con 2016 runs from 21 until 24 July. (Photo by David Maung/EPA)

An attendee dressed as Junkrat from the game Overwatch poses for a picture during opening day of pop culture convention Comic Con International in San Diego, USA on Thursday, July 19, 2018. (Photo by Mike Blake/Reuters)

Attendee Emily poses for a picture at 2017 Comic-Con International on July 20, 2017 in San Diego, California. (Photo by Mike Blake/Reuters)

Friends outside the convention center during opening day of the annual Comic-Con International in San Diego, California, United States July 21, 2016. (Photo by WENN/SIPA Press)