"Aquaman: Superman was right. Brainiac needed to die. But I couldn't stomach the idea of Kal's return to power. Atlantis would not again be his vassal. With Batman beaten and his allies imprisoned, I couldn't muster the force I needed to take Superman down. I'd all but lost hope when my marines discovered an abandoned Insurgent base hidden in the Southern Ocean. Here Lex Luthor perfected his inter-universe transporter. From plans left behind, my scientists built a new device. Now I go and ask for the help of those I had fought. I must also ask their forgiveness."
January 1, 1970
https://en.wikiquote.org/wiki/Injustice_2