Although 's story is a continuation of Rocksteady's Arkhamverse, several plot points open the door to an extended DC Multiverse. The main campaign follows A.R.G.U.S. and Task Force X as they are deployed into Metropolis in the midst of an alien invasion led by Brainiac. In this time, Brainiac has captured and brainwashed 99% of Metropolis' citizens, including the majority of the Justice League, creating plenty of additional enemies for Task Force X to overcome on their mission to stop Brainiac's plans to terraform Earth and to create a New Colu.
Colu was home to the most intelligent race in the universe. In the Arkhamverse, this planet has been destroyed, and Brainiac is determined to rebuild the advanced civilization he has lost at any cost.
[Warning: The following article contains major spoilers for Suicide Squad: Kill the Justice League]This mission seems straightforward initially, as Amanda Waller puts out a kill order on the Justice League and Brainiac, and it seems like Task Force X's only challenge will be overcoming some of the DC Universe's most powerful heroes. However, it soon becomes clear that the scale of this assignment is far larger than it initially seemed when the multiverse is established soon after killing Flash. Task Force X is teleported to another dimension referred to as «Earth 2» in the game. Here, they find a world already decimated by Brainiac, where they find a surviving Lex Luthor. As the Luthor of Task Force X's main universe — which is deemed «Earth 1» — has been killed, they bring him back to their universe to assist them with their mission and refer to him as «Lex-2».
After successfully killing the Justice League, Brainiac teleports Task Force X aboard his giant Skull ship to meet them face-to-face for the first time. Alongside detailing his plans to create a New Colu, he also tells the team what an asset they could be if they submitted and agreed to fight alongside him. It then becomes clear that Brainiac's ambition is far greater
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