Power source of War Hulk is Celestial technology, a lot like Apocalypse. The whole purpose of him (in case you don't know) was so that he could battle the Celestials, of course, under Apocalypse control.
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Picture drawn by Richard Watts, the Heavy Metal Ninja
http://www.chrysander.com/
Celestials are more powerful than Cyttorak. Also, it really doesn't state that War Hulk beat those two, but he did knock them around. It didn't really go that far into the story after he became War Hulk. I personally think he would have won though.
Celestials also beat all the gods of Asgard and Olympus as well as the Destroyer.
Cyttorak is an alien, not really a god on earth as is Odin, Zeus, etc.
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Picture drawn by Richard Watts, the Heavy Metal Ninja
http://www.chrysander.com/
The only reason why he beat Thor is because of those magical enhancements, which is the main part to Juggernaut. Actually, Thor was about to beat him in one comic as the magical field went down, but then his field came back up, therefore making all magic attacks/physical and such on him invulnerable, and that is how he won one of their battles.
Again, that is just one god. Put Juggernaut up against Zeus and I doubt he is going to fare well, let alone both Asgard and Olympus with the Destroyer. If the Celestials can take out all 3 of those with relative ease, imagine them taking out Juggernaut.
Now, Celestial technology doesn't necessarily mean that it is as strong as the Celestials. Reason being is that they made technology for allies and such as speculated with "Ship" that Apocalypse has. They are about 2000 feet tall (and Exitar being 4000 ft tall), and Ship is definitely too small for them. So I doubt their technology is even close to their true might.
Heres a small description on them if you want to read: