Synopsis
In #21 Sub-Mariner stepped up when the rest of the Illuminati wimped out - he destroyed the incursion-Earth of the Great Society, thus saving his own Earth and both universes. Last issue he was nonplussed when his teammates got angry and kicked him off the team. Then another 8-hour incursion began.
Now the remaining Illuminati know they can't bring themselves to destroy another Earth. So in 8 hours their universe and the other 1 will die. They split up to deal with their fate, each in his own way.
Bruce Banner returns to the ruins of Gamma Base to toast the upcoming final death of the Hulk.
Beast chooses to tell the Hank McCoy from the past what's happening, and ask him whether he should warn the other X-Men or just let them die in peace. Hank is more concerned with why Beast chose to bring the original X-Men forward in time when he knew about the incursions and the impending end of the universe.
Dr Strange drinks tea and asks Wong if he's a good man. His manservant tells him he isn't.
Tony Stark pours himself a whisky-bottle-full of drinks, and determines to resist them to the end (I think).
Black Panther goes to see his ex-wife Storm, the best thing in his life. They regret that their responsibilities broke up their marriage.
Mr Fantastic goes to see his scattered family. He's already visited Franklin and the Future Foundation kids. Now he's brought Sue to Latveria where Valeria is staying with Dr Doom. Doom's adopted son Kristoff welcomes them, but Victor himself is surly. He and Sue agree that Reed's actions are worrying. Reed hasn't told anybody what's going on. but Val takes 1 look at the incursion countdown clock in his palm and asks "What have you done?".
Black Bolt weeps with Lockjaw in the Blue Area of the Moon.
Then nothing happens.
The Illuminati (except Dr Strange) congregate (in person or holographically) in the Baxter Building. Despite the destruction of other universes they've witnessed via Mr Fantastic's Bridge, their universe seems to have survived. They face the horrifying prospect that they may have killed a populated world for nothing.
But then Black Bolt signs a question concerning their missing member, which Reed interprets as wondering what Namor is doing.
We see Namor hosting a gathering of Maximus, Black Swan, Terrax, Thanos, Proxima Midnight and Corvus Glaive (apparently now collectively called the Cabal). And we see that they destroyed the incursion world.