Earlier this year, Mike Judge joined Trey Parker and Matt Stone at San Diego Comic-Con to discuss the current seasons of Beavis and Butt-Head and South Park. During the conversation, the three revealed that they’d discussed doing a crossover episode back in the ’90s in which Beavis and Butt-Head would’ve had to babysit Cartman. This quickly made headlines, with many expressing hope that the idea could be revisited now that both shows are airing back-to-back on Comedy Central. What nobody brought up at the time, however, was that the shows’ characters had already crossed over in the past, albeit in minor ways.

In 2013, Metallica bassist Robert Trujillo produced an animated short called ‘Tallica Parking Lot. The five-minute cartoon takes place in a parking lot outside of a Metallica concert that’s apparently being attended by the South Park boys and Beavis and Butt-Head, among others. Cartman, Kyle, Stan, and Kenny are shown first, watching Metallica drummer Lars Ulrich hit tennis balls around. When a truck pulls up and interrupts him, Ulrich angrily storms into the venue, slamming a door behind him and inadvertently causing Kenny to fall to his death. About a minute later, we find Beavis and Butt-Head hanging out in the middle of all the chaos that’s unfolding outside; they brought some nachos along with them and, somehow, their couch and lamp from home as well. Take a look below:

We finally got to see characters from each show appear together in a short promotional video for Paramount+ in 2022. Beavis and Butt-Head can be spotted standing next to Cartman very briefly as they gather around a campfire with some other TV stars and sing the theme song from the Halo video games:

The three characters also appeared separately in another Paramount+ promo spot that same year. As the narrator shows us different wildlife scenes taking place on “Paramount Mountain,” we see Beavis getting hit in the crotch by a golf ball, followed by Cartman—who’s referred to as a giant hippo—floating around on an inner tube:

Last year, Comedy Central treated subscribers to “31 Days of Doing the Holidays,” a month-long celebration during which Beavis and Butt-Head watched and commented on various TV shows, including South Park. While not technically a crossover per se, we did get to witness Beavis being turned on by Mr. Hankey’s wife at one point:

Judge likely didn’t work directly with Parker or Stone on any of these projects, but they did collaborate once back in 1999. It’s a bit of a little-known fact, but Judge actually provided the voice of Kenny at the end of South Park: Bigger, Longer & Uncut. He had three total lines, and of course his voice was sped up so you couldn’t even really tell it was him:

Here’s hoping they get a chance to work together again soon.