Well, let me apologize in advance for the long post but I have some pretty strong opinions regarding this story.
In my honest opinion, it ranks among the worst in-continuity Marvel cosmic stories I have ever read.
Why? It totally trashed Galactus' origin and motives, showed total disregard (or ignorance) for continuity, the story really didn't make sense in numerous respects even within its own internal framework, it introduced a new supposedly multiversal character (that was a clone of Starlin's nearly-as-terrible Hunger) only to have that character feel like throwaway villain of the week totally devoid of any grandeur whatsoever thanks to weak character motivations and a very anti-climactic death scene.
The story did initially present some potentially interesting ideas, but after Thor #6 all possible interesting or satisfying angles were thrown in the fire and we were left with a completely unsatisfying story that accomplished nothing but majorly damage Marvel's premiere cosmic entity without reason.
Cates clearly has some sort of fetish for totally demeaning Galactus, killing him and using his helmet as trophy, since this is the 2nd time he has done it.
See Thanos Wins for the first example.
**Regarding the Galactus origin retcon, which IMHO is the most unforgivable aspect of this story:
Galactus, who has for 40 years been consistently portrayed (reaffirmed by a dozen writers at least) as the sole survivor of the previous universe, the singular product of the merging of the Sentience of the Previous (6th) Universe and the mortal Galan, brother of Eternity and Death, the Third Force of the Universe who provides balance or cosmic consonance to reality, and the one being who is supposed to witness the natural heat death of the universe and provide the spark that will ignite the next multiverse is NOW supposed to be some lying coward who made a deal and got superpowers from some random villain of the week and has been hiding in the Marvel universe for the last 10-20 billion years trying to escape his real job? WHAT? Lol!
Cates has just turned Galactus into the ultimate con man.
Just think about it.
Cates' Galactus is a deserter herald of the Black Winter that has somehow managed to convince ALL of the Abstracts, the Living Tribunal and apparently even the One Above All himself that he is really an essential, integral pillar of his reality with perhaps the "most important" (per Eternity) destiny of all. What a con job, fooling all of these beings with cosmic awareness and omniscience like that!
Cates instead tells us Galactus is just a selfish, cowardly, cosmically irrelevant glutton on the run from a faceless universe eater, and that Galactus has stupidly chosen to stay in the same universe for billions of years to avoid said multiverse-traversing universe-eater (remember, Black Snowflake ate a DC earth and its Justice League). It all makes so much sense.
Does Cates not realize that he just totally overwrote all of the best, most compelling and most interesting aspects of Galactus? And for what? There was no payoff, there was nothing interesting added to Marvel lore. It was a diminishing retcon, does Cates not know ALL of these questions were already answered, and answered much better?
This is what happens when there is no editorial oversight of a shared continuity, you get unresearched writers ruining characters probably without even realizing it.
I guarantee Cates views Galactus as little but a giant glutton that that is the epitome of selfishness and is possibly using Galactus as an allegory for American consumerism in this story.
I can only assume Cates doesn't know the only reason Galactus didn't kill himself billions of years ago because is Galactus knows down to the very core of his being that he is a necessary component of reality who is destined to fulfill a grand, essential purpose and that at the end of time he will "give back infinitely more than [he] has ever taken".
That's Galactus, not this cosmic conman Cates gave us.
I was beyond disappointed with this story.
The only people that I could honestly see enjoying this story are Thor fans who like it for Battle Board points.
Beyond that, after reading the conclusion, I can not find a single redeeming quality in it.