OAKLAND, Calif. — There is no N.F.L. franchise quite like the Raiders and no scene quite like the one at their 52-year-old stadium on game days. In a league of 32 color-coded molds, the smoke-filled tailgate parties represent a vestige of original expression, described as something from a post-apocalyptic world.

In the morning haze of a recent Sunday, amid the maze of trucks, tents and barbecues, a man named Elias Sanchez talked about fandom as family. His 25 Raiders tattoos, some on his bald head, made him stand out only slightly in the crowd.

“Some of my Raider tattoos have Raider tattoos on them,” Sanchez said. One on his left arm read, “Til death do us part.”

Yet part they will. The Raiders, who do not have a home for 2019, could be playing their final game in Oakland on Monday night as part of the team’s sadistic, slow-motion departure for Las Vegas in 2020.