The finale of Young Justice: Outsiders gave Artemis Crock some much-needed closure regarding the death of her first love, Wally West. This came after a season full of teases that the first Kid Flash would come back from the dead or that Artemis might start a romance with the former Red Arrow, Will Harper.
Artemis and Wally first became a couple at the end of Young Justice season 1, when they were Kid Flash and Artemis and part of the first generation of teen superheroes to serve on the Justice League's covert Team. Season 2 saw the young couple retired from heroism and living together while going to college, though Artemis came out of retirement to assist their friend Kaldur with a deep-cover mission. Wally also came out of retirement in the season 2 finale, in order to help destroy an alien doomsday device that would have destroyed all life on Earth. It was here that Wally apparently died while running at top speed, his body seemingly vaporized.
Season 3 of Young Justice found Artemis sharing a house in Star City with Will Harper and her niece, Lian. At first, Artemis insisted that she was just trying to help raise the daughter that her sister, Cheshire, had abandoned, but as the season progressed it became clear that both Will and Artemis had been looking at one another with romantic intentions. Will made the first move in the season's penultimate episode "Overwhelmed," surprising Artemis with a romantic dinner for two on Valentine's Day. While Artemis was receptive at first and returned Will's kisses, she was soon hyperventilating from an apparent anxiety attack and was only calmed after she went to her room and saw the picture of Wally she kept on her dresser.
Realizing that she needed help getting over her first love, Artemis turned to the magician Zatanna, who had also been part of the first Team. Bringing their friends M'Gann and Raquel for emotional support, Zatanna confronted Artemis and told her that she couldn't use her magic to summon ghosts or raise the dead. The best she could do was send Artemis into Limbo and hope Wally's spirit might meet her halfway and even then there was a risk that Artemis might become lost in a world of illusion and might be lost to the material world if her soul didn't return to her body before sunrise. Artemis accepted this risk and Zatanna reluctantly agreed to work the spell, even as she warned Artemis that this might leave her more broken than before.
Artemis found herself in a realm of mist and clouds and was greeted by a white-clad Wally West. The world around them shifted into a replica of their old house, as they began to live out the life Artemis had dreamed for them, including getting married, graduating and having children. In the end, Wally shattered the illusion as he kept commenting on how it was getting lighter outside, finally wishing Artemis well and telling her that he wanted her to live a good life without him.
While this gave Artemis the chance to say goodbye she never had, all was not as it seemed. It was revealed at the end of "Overwhelmed" that Zatanna and M'Gann had used their powers together to create a "psychic playground" that Artemis would subconsciously shape herself, since Zatanna really had no power to summon the dead and Artemis had threatened to seek out an evil wizard that did have such powers. This means that Wally West might still be alive (perhaps absorbed into the Speed Force, as many fans theorized) and could return in season 4 of Young Justice. Even if Wally truly is dead, it seems that this subplot will continue into the next season, given the recurring issues involving M'Gann using her powers to manipulate her loved ones for what she sees as their own good.