The first issue was devoted entirely to the Alien Alliance, and the kidnapping of humans from Earth to be tested for a genetic anomaly....which some people on Earth were found to have, that allowed them to manifest super human abilities when hit with extreme stress or danger.
This first issue set the stage for First Strike and Aftermath (the second and third issues of the series), as well as the two issues of individual titles of the heroes of the DC Universe, some of which are detailed below.
Animal Man and Swamp ThingAnimal Man (the man with animal powers) and Swamp Thing (a powerful Earth Elemental both got a little involvement in the battle. In Animal Man #6 (Holiday 1988 by Grant Morrison, Chas Troug and Doug Hazlewood), Buddy Baker (a.k.a Animal Man) faced off against a Thanagarian warrior and artist, with a little help from Hawkman, while Swamp Thing #81 (Holiday, 1988, by Rick Veitch and Alfredo Alcala) didn't have Swamp Thing in it (as the Dominators sent him away the issue before, fearing their plant-based technology would be vulnerable to a plant elemental), and this issue dealt with his wife, Abby Cable, dealing with a widowed alien.
Wonder WomanBlack Canary in Wonder Woman #25 (1988 by George Perez, Chris Marrinan and Will Blyberg), helping the Justice League International against the warrior Khunds, while in Wonder Woman #26 (January, 1989, also by Perez, Marrinan and Blyberg), Wonder Woman works with Captain Atom and Etta Candy to free Steve Trevor from the shape-changing Durlans.
...and the 3 issue mini-series is collected in tradepaperback, with Animal Man's issue in the Animal Man TPB of 1991, Swamp Thing in Swamp Thing: Infernal Triangles TPB of 2007, and the Superman tales would make it into a Superman: The Man of Steel Volume 11 (if there is to be one), and the Wonder Woman issues would be in the second Wonder Woman by George Perez Omnibus due out in 2017, with the rest of the tales presented here needing collection.....
....and more tales to follow in a new column!