It took the X-Men, the Fantastic Four, and the Avengers to defeat Onslaught. Savage hulk broke his armor and then even Thor couldn't disrupt disrupt Onslaught, as energy, by himself.
He's got all of the powers of Professor X, Magneto, and because of Franklin he is able to alter reality to a degree. he can augment his strength to class 100.
that may be debatable saying he is more powerful then Galactus but you might be right but then again i dont think he is anyway Apocalypse is an inconsistent being they make him super strong in one issue taking a scream from deadbolt and not even being hurt then they show him being defeated by magneto and the likes of Strife then later they show him stalemating the high evolutionary its all a load of crap the best depiction of Apocalypse is when he is battling the x-men on the tv show not evolution or the original with magneto but the one they use to show on fox were he would hand the x-men there butts on a regular basis almost killing them on almost every encounter it was inconsitent even in the cartoon when Magneto almost threw him down off a ledge in the axis of time in a past ep Apocalypse could fly, he is said to have almost unlimited strenght but is he depicted as such i think not that would mean he hand War Hulk his butt since he has celestial tech that would mean he should withstand a blast from even odin since even all the sky fathers cant even hurt the celestials his character is totaly inconsitent with him at full power losing to cable give me a break losing to strife didnt he only lose to strife cause he had some special sword or whatever?
who would win even if Apocalypse was at full power i dont know probably Onslaught but maybe Apocalypse would servive but maybe again maybe he cant what can Onslaught do to Celestial armor?
So i'll list both of there powers. Source Answers.com
Apocalypse was one of the most physically powerful beings on Earth. Thanks to the Celestial technology's modifications to his body, he could alter the molecular structure of his body at will in order to change his form. Using this he could alter his appearance or the size of his body; transform his arms and fists into various melee weapons and grant himself superhuman strength. He also can generate energy, thanks to a combination of his mutant power and the Celestial technology in his body. He can use this energy to levitate himself and others, create force fields, and project bursts of concussive force, and can augment himself further by drawing on various outside energy sources.
Apocalypse has demonstrated the ability to teleport himself and other beings, although this ability may be generated by outside technology rather than by Apocalypse himself.
Finally, he was unaging. Even before being modified by the Celestial ship, he lived for thousands of years and was highly resistant to injury. With the Celestial modifications, this resistance to harm was amplified, although it is still possible, albeit highly difficult, to cause him injury that would not be immediately regenerated by his power. Should he suffer massive injuries that prove potentially fatal, he can enter a coma-like state of suspended animation during which he may recover from his wounds with the assistance of his Celestial technology.
In the future timeline from which Cable hails, Apocalypse's physical form had grown too aged and enfeebled to contain his vast superhuman energies. Hence, he transferred his consciousness and powers into a succession of host bodies, abandoning each one when it too grew too old to contain his power. This alternate future version of Apocalypse was ultimately defeated in transit from a depreciated body into a potential host body. Shortly before he transferred himself into Cyclops, he revealed that he was in a host body in the present day - it is not entirely clear when this happened, but the most likely time is when he appeared to die on the moon.
Aside from his superhuman powers, Apocalypse was also an extraordinary genius with knowledge of science and technology centuries ahead of conventional science. This was not merely a result of his exposure to alien technology, as he was able to make significant new advances beyond the alien materials he was exposed to.
Onslaught has shown a wide variety of abilities including super strength, energy projection, the ability to stun any desired team when combat begins, and mental manipulation. Though unrevealed, his source of power is probably telepathic in nature.
In addition to this, Onslaught has shown the ability to manipulate electromagnetic fields as extensively, if not more so, than one of his progenitors Magneto. Using these powers, he is able to control electricty, magnetism, gravity, heat, light, and other parts of the electromagnetic spectrum.
Using the powers of X-Man and Franklin Richards, Onslaught became unstoppable. There was literally nothing he could not do. He is thought to be superior even to Apocalypse in terms of power at his peak.
But he's not always at his peak, and apperntlu Apocalypse at one point was stronger than Onslaught. It did say at his peak, which means he's only said to be greater than Apocalypse during his peak.
What makes you think it's no contest if only one time have they said that they thought Onslaught was better than or close to Apocalypse power. Does he still have Franklin Richards power? It aslo said they only thought Onslaught was as strong as Apocalypse at his peak is he still at his peak?
I'm not saying your wrong I just want to know what you base your argument off of.