Synopsis
The previously page reminds us that Black Swan came to this Earth in the 1st incursion from the Earth of the other timeline, and used a device on that Earth to destroy it (#1). Since then they have used (and lost) the Infinity Gems to push back another incursion (#3), and seen an alternate Galactus (supported by an alternate Terrax) destroy the Earth of an 3rd invading timeline (last issue). Then Black Swan predicted another incursion, which turned out to be in Latveria.
Now Mr Fantastic and Iron Man take Swan out of her cell in the Wakandan Necropolis, to advise them when they enter Latveria. But 1st they show her the antimatter bomb they've built, which they reverse-engineered from the trigger she used to set off such a device in #1. She commends them on at last taking the step necessary to defend their universe. Beast articulates the unease of most of the Illuminati, but Sub-Mariner sneers that they still cling to the idea that they can destroy a world and still feel like heroes.
They transport themselves and the bomb to Latveria, outside the invisible wall hiding the incursion. But then they breach that wall (Dr Strange levitating the bomb) they find the other Earth is hanging in a blue sky, instead of the red one they've become used to. Which causes Black Swan to panic. She starts to explain that this means they face the Sidera Maris of the Mapmakers, and they don't have the 8 hours they normally have in which to act.
Meanwhile a horde of armoured soldiers descends on Dr Doom's castle, to be met in battle by Doom's 'son' Kristoff Vernard. Doom is besting more invaders inside the castle, and then teleports to the roof to join Kristoff. Black Panther isn't so much concerned about the fight as about the fact that Doom will now know about the incursions, and the Illuminati's involvement.
Black Swan leads the group across to the other Earth to show them what they face. They find a barren globe, which she says the Mapmakers have used up. She complains that these guys pervert the rules laid down by her god Rabum Alal.:- ne of the 2 Earths involved in an incursion must be destroyed within 8 hours, to save both timelines. But the Mapmakers use that system for conquest.
She describes how their troops the Sidera Maris cross over to establish a bridgehead in the incursion point on the new Earth. Then the old Earth is blown up, sending a large fragment crashing into the incursion point. This fragment enables more Mapmakers to later cross from the old universe into this one, a new world to plunder. And they don't wait 8 hours to destroy the old Earth, but do it in 1 hour!
(They are called Mapmakers because they keep a map of links between universes.)
This world being dead makes the Illuminati's decision easier, as they return to their own Earth. But Black Panther still feels uneasy as he uses Black Swan's trigger device to destroy the other Earth, before the Sidera Maris can complete their plan. And the incursion vanishes.
The 2 Dooms have killed all the invading troops, and they watch as the Illumati teleport out of Latveria.
Back in the Necropolis Mr Fantastic escorts Black Swan back to her transparent cell. He claims that he wanted to leave her free, but was outvoted. He's sure the others will come to trust her eventually.
But after he's gone she casts a sly glance towards the other prisoner Terrax (from #4-5). And reveals a hidden talent as she mentally talks with him. She suggests an alliance, and promises him his heart's desire - worlds to destroy.
And back in Latveria Doombots bring a fallen shard of the other Earth to their master.