The final episodes of Young Justice: Outsiders are building to an epic battle between the forces of Darkseid and Vandal Savage. The two despots have been allies for centuries but recent events within the supervillain team known as the Light threatened the balance of power across the galaxy and seem to have left Savage reconsidering his joining forces with the New God of tyranny.
Relations between the various villains making up the Light were strained even before Gretchen Goode abducted the heroine Halo, in defiance of the group's rules regarding respecting one another's claims to property and revenge against certain enemies. The Ultra-Humanite had originally asserted ownership of Halo as a test subject, but Goode believed that Halo held the key to the Anti-Life Equation - a cosmic artifact long-sought by Darkseid, which would give whoever possessed it the power to crush the will and command the soul of any who opposed them. When the Ultra-Humanite confirmed to his teammates that Goode had seemingly been able to utilize the Anti-Life Equation through Halo to take control of his protege, Dr. Helga Jace, Savage was clearly shaken by the news and far more disturbed than the rest of the Light.
It's no surprise that Savage knows more about Darkseid's goals and the power of the Anti-Life Equation than his partners in the Light. Young Justice season 2 (aka Young Justice: Invasion) ended showing that Vandal Savage had allied himself with Darkseid in order to gain the forces needed to fight the alien Reach. It was later revealed in Young Justice season 3, episode 7, "Evolution," that this alliance was not a new thing and that Darkseid and Savage had formed a partnership over a millennium earlier, with Savage apparently unaware that Darkseid had only agreed to spare the Earth because he thought the planet's metahumans might eventually lead him to the power of the Anti-Life Equation.
As Young Justice season 3, episode 23, "Terminus" opened, it became clear that while Vandal Savage might have started out ignorant of Darkseid's ultimate goals, he had learned something of the Anti-Life Equation and what it could do. To that end, Savage personally went to the Outsiders and offered them coordinates to the Orphanage - the space station run by Granny Goodness, where Halo was being captive. All Savage asked for in return was that when Halo was rescued that the heroes tell her abductor that it was Savage who had told them where Halo could be found.
It is unclear precisely what the nature of Vandal Savage's game is. Did he aid his enemies because he feared confronting someone armed with the Anti-Life Equation personally? Or did he mean to show his superiority to Darkseid by proving he could control his enemies without some mystic math formula? Whatever the case, it seems that a conflict is brewing between the two villains and the heroes will be caught in the middle as Young Justice: Outsiders comes to a close.