they got supermanwhich is a huge plus.but i see superman getting beat one on one.
the dc heros seem like they would go out more headstrong opposed to actual planning (except for batman)
i think they would take onslaught without a doubt but would he pose as much as a threat to them
No, he didn't. He took on Earth's heroes. X-Men, FF, Avengers, Hulk, etc.
I have no idea why the Pantehon of Earth Gods didn't get involved. Needless to say, if Onslaught even looked at Galactus wrong, he'd be killed with little to no effort.
I'd say it would be bad news for Onslaught if Quasar, Surfer, Warlock/The Watch (Gems and all), Thor (who was absent for most of the Onslaught saga) and the likes showed up.
True, the DC universe contains a lot of characters that, in terms of pure power, are often matches for those found in the marvel universe. Wonder Women and Superman alone spring to mind. Also, as there are few mutants in the DC universe one imagines Onslaught would have a harder time possessing the heroes.
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From even the greatest of horrors irony is seldom absent.
if onslaught took out the justice league it would make him a lot harder to kill.
what if somehow onslaught started to absorb superman or wonderwoman?
sure you can say it couldn't happen but transporting in other dimensions or universe could slightly change his powers