Young Justice: Outsiders is promoting Kaldur'ahm from Aqualad to Aquaman. Kaldur'ahm (or has he's more commonly known Kaldur) was introduced in the very first episode of Young Justice. Although Aquaman's sidekick Aqualad has been around for decades, Kaldur was a completely original character created for the show. During the first season of the animated series, Kaldur became the leader of the Young Justice team and in the process changed a lot of fans' minds about Aquaman and his related characters being a group of lame fish people.
During Young Justice season 2, Kaldur got pushed a little bit to the wayside. Most of the season had him working undercover with his father, Black Manta. Yet the real intention of the mission was kept a mystery from the audience for most of the season, giving the impression that Kaldur had broken bad. In the long-awaited Young Justice season 3 there won't be any moral ambiguity with Kaldur. Kaldur won't just be a hero but one of the most important heroes in the DC Universe.
EW revealed in an exclusive story that Kaldur will get a superhero promotion to Aquaman during season 3. Kaldur has been suspiciously absent from most of the promotional material leading up to the Outsiders season. Evidently, his new superhero identity is to blame because season 3 will see Kaldur in a radically new role. Young Justice producer Greg Weisman explained:
"We established back in season 1 that King Orin was training Kaldur to take his place as Aquaman. Aquaman was also King of Atlantis, which to most people would be a full-time job, and yet he also had to be in the Justice League as Aquaman, which was a lot on his plate. His game plan was to train Kaldur’ahm to be the new Aquaman so he could go back to being King of Atlantis, which was plenty. What you’ll see in this season is that after everything that’s happened in season 1 and season 2, and the leadership qualities that Kaldur has shown, Orin looks at Kaldur and says, ‘You’re ready.’ It’s a pretty momentous year for him."
It's unclear how Kaldur's new position as Aquaman will factor into the overall story of Young Justice. While the larger DC Universe has always been included in Young Justice, the focus has been on the younger generation of heroes. Kaldur becoming the new Aquaman so that the original can tend to his kingly duties, seems to suggest that Kaldur will graduate out of the team he helped found in season 1. This could explain why early trailers have focused heavily on Nightwing and Superboy working together as the only heroes from the original Young Justice team.
Of course, it's also likely that Young Justice: Outsiders will tell a story where every hero from the DC Universe needs to be involved. Young Justice season 1 and 2 both heavily hinted at the imminent arrival of Darkseid. Darkseid is the leader of the dimension Apokolips and one of the most powerful villains in the DC Universe. Aquaman, whether it's Kaldur or Orin, would definitely join the fight against the leader of Apokolips. Although nothing about the promotional material for Young Justice: Outsiders has suggested that Darkseid will arrive, it seems inevitable that the Big Bad will be involved in some capacity. Darkseid's lingering invasion was one of the biggest cliffhangers when Young Justice was originally cancelled in 2013.
Kaldur isn't the only hero that will be going through some changes in Young Justice: Outsiders. The team itself is going through an overhaul with a ton of new characters from the DC Universe being recruited to work with leader Nightwing. As the subtitle of the season suggests, many of these new heroes will be lifted from the 1980s comic, Batman and the Outsiders. Katana, Geo-Force, and Black Lightning are all coming to Young Justice season 3 and they're just a few of many. Those new heroes can be seen fighting alongside old favorites in a new promo, which is embedded below.
Young Justice: Outsiders will premiere January 4th on DC Universe.