Warning: The following contains SPOILERS for Young Justice season 4.
The classic Superman villain General Dru-Zod was recently revealed to be an intergalactic menace in the reality of Young Justice, who nearly defeated the Legion of Super-Heroes, establishing himself as even more threatening in the cartoon than his Superman movie appearances. General Zod is widely regarded as one of the most dangerous of Superman's enemies, having been the chief antagonist of the movies Superman II and Man of Steel. Despite this, the General Zod of Young Justice has proven himself to be the most dangerous incarnation of the character to date, being impossible to defeat in direct battle and difficult to contain.
General Zod's rise to power was detailed in two drastically different accounts in Young Justice season 4, episode 19, "Encounter Upon the Razor's Edge!" One version of the story was dictated to Kid Flash by the Legionnaires Saturn Girl and Chameleon Boy. The other was recalled by General Zod's son Val-Zod, to his companions Mantis and Ma'alefa'ak. While their descriptions of General Zod were understandably incompatible, they did agree upon the same broad history of events.
Reportedly, General Zod and his followers were sentenced to temporary imprisonment in the Phantom Zone after their attempted coup of the Kryptonian government was exposed by Chief Scientist Jor-El. Zod and his followers were trapped in the Phantom Zone for over a millennium, due to the destruction of the planet Krypton eliminating anyone who might have kept track of their sentences. They were not released until the United Planets of the 31st century learned of the Phantom Zone's existence and arranged the release of all the prisoners contained within to a colony on the planet Daxam. Zod responded by raising an army of Kryptonians and Daxamites and attempting to overthrow the United Planets. His efforts were thwarted by the Legion of Super-Heroes, who banished Zod and his followers to the Phantom Zone a second time and destroyed the last remaining Phantom Zone Projector. While Young Justice's Zod was defeated, the cartoon's depiction of him is even more warmongering than other iterations, suggesting he poses even more of a danger than these other versions of the villain.
Young Justice paints a far darker portrait of General Zod than any previous portrayal of the character. While Zod has always been a petty tyrant convinced he was born to rule, most incarnations of the character have had some noble traits or sympathetic motivations. The General Zod of Man of Steel played by Michael Shannon is a prime example of this, having been motivated by the goal of saving his people from extinction, which would have been admirable if he were not willing to destroy the people of Earth to do it.
By contrast, the General Zod of Young Justice was granted his freedom and given a position of authority leading a Kryptonian colony by the United Planets. This might have been enough for other incarnations of General Zod, but not this one, who reportedly became the ruler of the 31st century universe in an alternate future where the Legion of Super-Heroes never existed. The battle to avert this future seems poised to be at the center of what remains of Young Justice season 4.