Agamemno then engineered a switch wherein the villains' minds switched with those of the JLA. In the true JLA's absence, other Silver Age heroes came to clash with the now seemingly evil heroes. Eventually, Green Lantern used the power of the Oa's Central Power Battery and a Thanagarian weapon called Absorbascon to reverse the mind-swap.
Having spent time in their enemies' bodies, the villains knew their heroic counterparts inside-out. To regain the edge, the JLA used the power of Robby Reed's alien H-Dial to transform themselves into totally different heroes. Then using his power ring through the Absorbascon, Green Lantern removed all knowledge of the heroes' secret identities from the villains' minds.
Lex Luthor, Joker, and Cheetah III (widely regarded as the archenemies of the JLA's three primary members: Superman, Batman and Wonder Woman) recently formed an "Injustice League Unlimited", as first seen in the Justice League of America Wedding Special. While it seems the membership is much greater in the promotional image of Justice League of America (vol. 2) #13, the Core Members of the team shown by Wizard magazine is a select group of various arch-nemeses.
The team was created by Dwayne McDuffie, a writer from the animated series Justice League Unlimited, which featured a similar expanded Legion. Lex Luthor has the idea to bring the villains together, claiming it was a protection racket first but with the ultimate aim of conquering the United States. During the storyline, the Injustice League splits up and manages to capture the Justice League members in small groups. However, the JLA is freed by Firestorm, and it battles the Injustice League at its swamp headquarters. In the ensuing melee, many of the villains flee (later to attack Black Canary and Green Arrow's wedding), but most are taken captive by the League. It is revealed at this time that Lex Luthor actually had a secret goal in forming the league. He refuses to reveal details, but mentions that he planned for his capture. The remaining villains are then taken away by Amanda Waller and the Suicide Squad, who plan to ship them away to a distant planet, as seen in DC's Salvation Run storyline.
It is notable that the alternate covers of the second issue of the arc, Justice League of America #13, feature many more villains than were actually in the League, including Amazo, Bizarro, Black Adam, Sinestro and the Rogues (Heat Wave, Captain Cold, Weather Wizard, Abra Kadabra and Mirror Master).