Synopsis
The previously page mentions some significant events from Infinity #1 (most of the Avengers head into space to face the Builder fleet), Avengers #18 (the Builders rout the combined forces of the Galactic Council [including the Avengers]), and New Avengers #9 (Thanos sends the Black Order to Earth to find the 1 surviving Infinity Gem, and follows himself to exact the Tribute).
An advance team invades the SWORD Peak satellite. Abigail Brand and Sydren expel them, but not before they deactivate the Peak's automatic defences, allowing Thanos' fleet to get through to Earth.
In NAv#9 Thanos learnt that the Illuminati had gained and lost the Infinity Gems, with all but 1 destroyed, the Time Gem. We now see more events from NAv#9 as the Black Order approach some of the members of the Illuminati:- Corvus Glaive and Supergiant attack the Jean Grey School for mutants, where Beast is. Proxima Midnight goes to Sub-Mariner in Atlantis, to find them defeated in a war with Wakanda. Ebony Maw tries to talk Dr Strange into siding with Thanos (and this issue suggests he succeeds). Black Dwarf is repelled by Black Panther and his Wakandans. Meanwhile in New York Iron Man and Mr Fantastic use the defences of Avengers Tower to counter attacking spaceships.
The remaining member of the Illuminati, Black Bolt of the Inhumans, receives Corvus Glaive as an emissary of Thanos in his court in the city of Attilan hovering over New York. Glaive tells Black Bolt that Thanos knows his secret (which from #1 and NAv#9 we believe is that BB knows where the Time Gem is). Medusa speaks for BB and warns Glaive that if his forces attack Attilan they will be killed. But Glaive demonstrates that Thanos' men are eager to die for their lord, as he gets several of them to commit suicide.
Glaive gives the Inhumans 1 day to provide Thanos with a Tribute - the heads of all their children between 16 and 22.
We now turn to some more details of Av#18. The Galactic Council ambushed the Builder fleet and appeared to be winning. But then the ambushers were ambushed in turn, as the vast majority of the Builder fleet decloaked, destroyed 1/3 of the Council fleet and sent the others packing. (The Council's gaffe is made more believable here as we learn that the Builder fleet had always travelled mostly hidden.)
The Avengers had fought in 2 quincruisers, with some like Thor in open space. Now Captain America's quincruiser has returned to the Shi'ar rendezvous point, along with their free-flyers. But Captain Marvel's quincruiser is missing.
Gladiator, Majestor of the Shi'ar, is consulting with Mentor and Oracle about whether to stay in this out-of-the-way system or jump to the Galactic Council's central rallying point. (Some of the Shi'ar ships are currently unable to jump through space.) But 4 Builder craft suddenly pop up, chasing a crippled Shi'ar vessel. And Gladiator sends his forces in to fight, along with the Avengers.
Ex Nihilo, who was made an Avenger in Av#17, is held back from the battle. The Shi'ar know that he was created by the Builders, and worry that he will side with them. Ex Nihilo points out that he and his fellow Gardeners were sent out by the Builders and helped the races of the galaxy evolve into what they are, including the Shi'ar. The Builders are the gods of the galaxy. A Shi'ar counters that they have outgrown those gods, and have their own gods now. (Though it is unclear to me whether he refers to Gladiator who triumphantly signals the Shi'ar victory or their gods Sharra and K'ythri by whom he swears.)
But our forces now learn that the Builders win even in defeat. 1 of the Builders' Aleph robots lands on the agricultural planet at the heart of the system with a Gardener Jerran Ko (not the unnamed one we have seen in #1 and Av#18). It pains the Gardener to unleash a plague which soon consumes the world. The Shi'ar and Avengers can only save a few children.
Back on Earth Black Bolt enters the pocket reality that his brother Maximus the Mad found for him in NAv#8. Here BB can speak without destroying everything around him. He uses the device embedded in his palm to summon the other Illuminati here (as seen at the end of NAv#9). Hidden Maximus listens in as BB explains Thanos' demand. He gives Mr Fantastic a shard holding the records of the Inhumans (related to the last thing the Outrider saw in BB's mind in #1), where they will find what Thanos is looking for (the location of the Time Gem). But he also says that Thanos wants the death of the Inhuman children in order to be sure of killing his own son.