Warning! Spoilers ahead for War for Earth-3 #2
In the culmination of DC Comics' War for Earth-3, it's been proven that an evil Green Lantern would have no problem taking down Superman. Intending to save the dark world using any means necessary, Amanda Waller came up with a plan to liberate the alternate Earth-3 from Ultraman, the evil Superman and leader of the Crime Syndicate (an evil mirror of the Justice League). However, several members of the Syndicate shared no love for Ultraman, including John Stewart's Power Ring (Earth-3's Green Lantern counterpart).
Previously in this new event, Amanda Waller brought her handpicked team of agents and brought them to Earth-3. While she initially made it seem like she wanted to ally with Ultraman, it was later revealed that she just wanted his guard down before eventually betraying him. However, matters were complicated by the arrival of Rick Flag's Suicide Squad and the Teen Titans (seeing as how Waller didn't leave Earth-0 on the best of terms).
Related: The Evil Green Lantern Just Flexed on Hal Jordan's Favorite Ring Attack
As revealed in War for Earth-3#2 from Robbie Thompson and Dennis Hopeless, Waller's plan to take down Ultraman centered around using the Phantom Zone Projector, a classic device the primary Superman has often used to entrap foes such as General Zod. As such, it's been proven that it can imprison even the strongest Kryptonians. Even so, Flag still didn't trust Waller even after her true plan was revealed, resulting in him breaking the projector and dooming them all to Ultraman's rage. However, Power Ring surprisingly made a construct of the Phantom Zone projector, fulfilling the same purpose as the original: trapping Ultraman in another dimension and saving
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