DC League of Super-Pets’ director explains its startling post-credits scene

polygon.com:

The animated family movie DC League of Super-Pets — an origin story for Superman’s best friend, Kryptonian super-dog Krypto — is built for adult viewers as much as for kids. It’s packed with DC Comics gags, some of which are visual, like the Jonah Hex-themed steakhouse in downtown Metropolis. Others are musical: At one point, Krypto sings a little impromptu ditty about how much he and Superman love each other, to the tune of John Williams’ classic theme from 1978’s live-action Superman. Some are referential: At one point, Lex Luthor (Marc Maron) complains that he doesn’t have superpowers, not even the ability to “throw playing cards really hard” — seemingly a dig at Marvel characters like Bullseye or possibly Gambit, who each have used cards as weapons.

But viewers will have to wait through the credits for one of the more audacious gags, where League of Super-Pets openly makes fun of another DC property — and Dwayne Johnson, who voices Krypto, mocks himself. The movie’s co-writer and co-director, Jared Stern, tells Polygon how it happened.

[Ed. note: Spoilers ahead for the post-credits sequence in DC League of Super-Pets.]

In the post-credits sequence, set after the film’s resolution, Superman (voiced by John Krasinski) and Krypto are enjoying a Metropolis park by night when DC antihero Black Adam flies in with his pet dog. The two human heroes share one terse, tense acknowledgement, but the two dogs immediately start talking. (The film establishes early on that animals can communicate with each other; humans listening to their conversations just hear barking, meowing, or other animal noises.)

Black Adam’s sidekick Anubis brags about how his partner is a cool, edgy antihero, while Krypto chuckles that “antihero” is just