Superman: How General Zod Slid Into the DC Animated Universe
Timothy Donohoo
One of the most well-known enemies of Superman is General Zod, the Kryptonian military man with an intense feud with the son of Jor-El. Although he was once an obscure Silver Age villain, he first rose to prominence from his portrayal by Terrence Stamp in the Richard Donner Superman movies. Upon returning to the spotlight in comics in the 2000s, he's since appeared in Smallville, the Arrowverse, the DCEU and several other adaptations.
He never had much of a role in the DC Animated Universe, however, which stemmed from Superman comics and adaptations at the time divorcing themselves from previous iterations. Although he was essentially replaced by Jax-Ur in Superman: The Animated Series, Zod eventually showed up in the DCAU comic books.

General Zod in Superman Adventures

The first appearance of the DCAU Zod was in 1998's Superman Adventures #21 by Evan Dorkin, Sarah Dyer and Bret Blevins. The series told stories in the same continuity as the animated series. Here, he was, as usual, a Kryptonian criminal who had been trapped in the Phantom Zone. Zod was finally freed from his imprisonment by Granny Goodness, who had previously tried and failed to assault Metropolis via the Apokoliptian warrior Kanto.
Zod joins up with fellow corrupt Kryptonians Jax-Ur and Mala in an attempt to take on both Superman and Supergirl. Jax-Ur in the DCAU was rewritten from a scientist to a General Zod stand-in, heavily resembling Terrence Stamp's version of the character. Mala, on the other hand, was a mostly original villainess who shared the name of a Golden Age character. Zod also resembled his theatrical counterpart, while at the same time incorporating the Kryptonian design elements from the DCAU that were based on John Byrne's designs from the comics.
The trio of evil defeat Supergirl, but she returns and subdues Mala and Jax-Ur with Kryptonite. In this continuity, Supergirl was from the Kryptonian sister planet Argo, which was based on the Silver Age Argo City. This meant that she was immune to Kryptonite, but unfortunately for her, so was Zod. She finally defeated him by knocking him into a creature's cell in Superman's Fortress of Solitude, with said beast's cell having an artificial red sun that depowered Zod. Afterward, Zod, Mala and Jax-Ur are all sent back into the Phantom Zone.

General Zod in Justice League Unlimited

DCAU General Zod
DCAU General Zod
This incarnation of Zod would show up again in the pages of the Justice League Unlimited comic book that tied into the cartoon. Justice League Unlimited #34, by James Peaty and Gordon Purcell not only brought the character back, but even included his trademark catchphrase, "Kneel before Zod." The story of the comic had the Phantom Zone randomly being opened, unleashing the criminals within and allowing them to wreak havoc.
Superman takes it upon himself to take down the threat, as immense as it is. Unfortunately, Zod and the other Kryptonian criminals gang up on him, with the Argoan general even forcing chains with Kryptonite in them upon Superman. Green Lantern, Hawkgirl and the Martian Manhunter are able to fend off the rogue Kryptonians, taking the weakened Superman out of the area as they use the Atom's help to enlarge a piece of Kryptonite. The whole plot is revealed to be the work of Mr. Myxzptlk, who was the only one with the power to warp the properties of the Phantom Zone.
This would be the last time that Zod showed up in this continuity for a while, but another version of him has recently shown up in the DCAU continuation Justice League Infinity. With the villain's renewed popularity, however, this version is no longer the only one on the block, making him now one of several versions of the villains bent on making Superman bend his knee.