The DC Animated Universe
When trying to recruit Superman for his team, LeBron and Bugs happen upon Daffy Duck and Porky Pig staging a runaway train in Metropolis. While Daffy, Bugs, LeBron, and Porky realize they have no way to stop the runaway train, we catch a glimpse of Jimmy Olsen, Lois Lane, Supergirl, and Alfred. The train runs through Metropolis, Gotham, and Atlantis just as the real Superman is able to stop it right before it runs into an orphanage. The rest of the Justice League looks on unamused as LeBron, Daffy, Bugs, and Porky head back to their ship.