Doom managed to fight off the Beyonder with Galactus's powers.
Plus atleast Galactus had balls enough to go fight the Beyonder unlike the other abstracts.
He did not "fight off" beyonder. He got easily owned just trying to approach beyonder. Beyonder didn't even attack him.
The other abstracts didn't fight Beyonder because they were trying to assist his development into a complete cube being by acting like he was above them.
this is completely false. The phoenix force acted to save the previous universe from destruction. A by product of this act was enabling Galan to merge with the Sentience. Your wording has it look like the PF directly intervened with the intention of preserving Galan. This is totally false and you may have gotten that idea from others on this board propagating that same falsehood.
[URL=http://marvel.com/universe/ OHOTMUata_Corrections_Fantastic_Four_2005]OHOTMU
on the Phoenix Force and Galactus[/URL]
Actually, he most definitely is. The Sentience of the Universe, with whom Galan merged, is the Eternity of the previous universe...i.e., current Eternity's predecessor. That is why the Human Torch referred to Galactus as "the metamorphosed embodiment of a cosmos" which literally means, an entire universe incarnate, or made flesh. The only being who literally comprises the universe is Eternity. Galactus just happens to be the previous Eternity, merged with a mortal man. Not quite abstract...and not quite a mortal, physical being.
That is why Galactus and Eternity converse with each other as equals and with great mutual respect. That is why Death calls him "husband and father, brother and son." It's not solely because of his station, its because of what he actually is.
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"It is unwise to battle the Power Cosmic." - Silver Surfer
I know there is no thing as "Full power" Galactus. I made a mistake, what I meant was a Galactus out of character like BCA.
BCA Galactus would rape Infinity along with Eternity and Death.