Synopsis
This issue has flashbacks to Steve Rogers and Tony Stark creating the new Avengers team interspersed with the current action. I'm going to separate them out.
The flashbacks repeat the scene of Tony convincing Steve that the Avengers needs to be bigger, to meet bigger threats. Steve can inspire them to greatness, but Tony will design the Avengers to be effective. Stark also proposes a small core group, with extra members that can be called on as needed.
Captain America and Iron Man are obvious core members along with Thor. They also quickly agree on Hawkeye and Black Widow. And Tony insists on Hulk. The rest will be the backups. They also agree there should be a mix of old and new members in the backups, to help the new ones bed in.
The totally new Captain Universe, Hyperion and Smasher we met last issue are already on the list (maybe even already contacted?). Stark mentions that Luke Cage turned them down, and Dr Strange is busy. We see the pair getting other recruits on board, each for their own reasons (some possibly facetious). Wolverine's here for the beer, Spider-Man for the money. Falcon accepts because Cap asks him. Shang-Chi just accepts, but Stark suggests he could create some weapons to enhance his martial arts. Cannonball and Sunspot are tired of being outlaw X-Men, but fancy the Avengers spotlight. Manifold isn't sure he's up to it, but he'll try. Spider-Woman's in because she's an Avenger, Captain Marvel because she's a soldier. That completes the roster that's been brought in for this crisis. (Although there are still icons on the Avengers team board we've don't know anything about yet.)
The current plot opens on Mars, where Black Widow, Hawkeye, Hulk, Iron Man and Thor are captives of the aliens Abyss, Aleph and Ex Nihilo. Last issue these guys sent 2 'origin bombs' to transform parts of Earth. The Avengers came to stop a 3rd bomb, and found the aliens on an area of Mars they'd turned green with vegetation. After defeating Earth's champions the alien 3 sent Captain America back in the Avengers' quincraft as a message. Cap survived the crash, and activated a large group of backup Avengers.
Now Abyss has been studying the prisoners, and is intrigued by Thor. She deduces he is a god. Ex Nihilo asks Thor about his pantheon's creation myth. Then he enquires about their fate - is it a final end, or is there a resurrection to a new cycle. Thor doesn't answer this last question, probably because it's a sore point.
Instead Ex Nihilo explains the true story of the universe. A long time ago (probably in a galaxy far far away) the Builders were the 1st sentient race in the universe. After outgrowing the worship of the Universe as a Mother, they sent out mechanoid Alephs as gardeners of the cosmos. Mostly their gardening consisted of pruning, destroying races deemed unfit. But eventually one Aleph (the one in this issue) found one race worthy.
On that planet Aleph released 2 seeds he carried with him, which grew into Abyss and Ex Nihilo. Since then the trio have travelled countless other worlds. When they find a sentient species they either destroy it or help it evolve. And evolution is what the origin bombs are about.
On Earth Captain America is overseeing the modification of a quinjet to take the whole new team to Mars. Then 5 more origin bombs hit, and start evolving other parts of the Earth. On Mars Ex Nihilo explains that each one is different, evolving Earth-life in different ways. If none of them are fruitful, Aleph will destroy the world.
Back on Earth Cap can't wait any longer, even though Wolverine thinks the new team isn't ready. There also isn't time to wait for the quinjet to be finished. Cap calls on Manifold to use his power to transport them all to Mars.