¿Who is stronger, Onslaught or Fallen One?

Onslaught is a comic book character created by Marvel Comics and is known to be one of the publisher's most powerful and feared villains. He is a cosmic being created by merging the minds of Charles Xavier and Magneto, two of Earth's most powerful mutants. Onslaught has a number of supernatural powers, including the ability to manipulate people's minds and behaviour, superhuman strength and the ability to manipulate magnetism. He is also virtually indestructible, making him a formidable foe for any hero who confronts him.

The Fallen One is a powerful and mysterious cosmic entity from the Marvel Comics universe. It is an ancient being of immense power and possesses a wide range of superhuman abilities, including super strength, super speed, energy projection, and the ability to manipulate reality. The origins and true nature of the Fallen One are shrouded in mystery, and little is known about its past or motivations. It is believed to be one of the oldest known entities in the universe, and has been worshipped by many civilizations throughout history as a deity. Despite its god-like powers, the Fallen One has often clashed with the superhero team the Fantastic Four and other cosmic entities in its quest for power and domination. It is a formidable and dangerous foe, and has proven to be a constant threat to the safety of the universe.