Thanks to Crisis on Infinite Earths, Superman & Lois season 1 was able to tackle a big issue related to the DC hero in the pre-Crisis Arrowverse.
Following Crisis on Infinite Earths, Superman & Lois season 1 handled a big issue related to Clark Kent and General Zod on Supergirl in the pre-Crisis on Infinite Earths version of the Arrowverse. Before Tyler Hoechlin’s Superman had his own show, he was a recurring guest star on Supergirl, which had referenced his history as the Man of Steel. Throughout Supergirl’s run, they had made a point to bring up some of the events in Superman’s life, given that Clark had been a superhero for several years before Kara Danvers. While not everything was established about Superman’s career on Earth-38, that wouldn’t matter in the long run. By the end of Crisis on Infinite Earths, all the heroes were in the same world – Earth-Prime.
Since the game-changing Arrowverse crossover, the continuity got a soft reboot, allowing the creators to rewrite various characters and storylines. Given how little was known about Clark’s life as a superhero, it practically became a clean slate for Superman & Lois. Since the show’s premiere, they have already changed various aspects about Superman’s life that Supergirl established in previous seasons. From recasting both General Sam Lane and Morgan Edge, they have also altered some of Superman’s history, particularly his background with the DC villain General Zod. Pre-Crisis on Infinite Earths, Supergirl had explained that sometime in 2018, Superman and General Zod had a showdown, with the former killing the latter.
Supergirl season 3 referenced that, at some point, General Zod was resurrected and fought the Legion of Super-Heroes in the 31st century. However, that wouldn’t matter as Zod’s Earth-38 history was erased thanks to Crisis on Infinite Earths. In Superman & Lois episode 12, “Through the Valley of Death,” they discover that General Zod’s mind was stored in the Eradicator before Krypton’s destruction. While his current status is unknown, Superman & Lois was right to retcon Supergirl’s references to General Zod. In the comics, Zod has always been one of Superman’s most iconic enemies, given that he’s one of Krypton’s remaining survivors. Having Superman kill off General Zod is a huge thing that should be told on-screen, not just referenced.
In all of the live-action TV shows and movies that General Zod has appeared in, he has always been one of Superman’s most complex antagonists. Zod represents one of Clark’s limited connections to Krypton, which is why it was a powerful moment when Superman snapped his neck in Man of Steel. As General Zod was beyond saving, Superman had no choice to do what he did while also losing his last ties to his home world. That’s why it was strange that Supergirl would establish their history on such a large scale in the Arrowverse, but only off-screen. Superman having to kill Zod is something that has to be done on-screen because it would have a huge impact on Clark. Thanks to Crisis on Infinite Earths, Superman & Lois not only erased that but allowed themselves to bring Zod back in a future season.
It’s similar to how Crisis on Infinite Earths referenced that Superman had battled Doomsday, but managed to defeat him. By retconning that, it lets Superman & Lois save another prominent DC storyline for later seasons. While Clark succeeded in getting Zod’s mind out of his head, Superman & Lois will likely bring him back once Morgan Edge’s arc is over. Since Crisis on Infinite Earths erased Supergirl’s Arrowverse references to Zod, Superman & Lois can also cast a new actor as the famous villain.