Franklin Benjamin Richards
Franklin is a mutant beyond Omega-Level with vast reality-manipulating and psionic powers.1
1Powers and Abilities
Two Celestials, Ashema the Listener and Nezarr the Calculator, were at one time tasked with retrieving Franklin for evaluation as a new member of the Celestial Host.2
2Heroes Reborn: The Return #1
He warps the three Celestials away to the inner sphere of a local gas giant. He then acquires an orb containing his younger counterpart's powers, which he stores within his chest. When the Celestials return, the adult Franklin again confronts them, and destroys them all in a prolonged battle.
In the aftermath, the adult Franklin shares a brief moment with Galactus. The two discuss the heat death of everything and the revelation of Franklin's immortality, specifically that he will, a billion years from now, stand beside Galactus to witness the birth of a new universe.
As a little boy creates a universe in his bedroom.
Again as a little boy offhandedly defeats multiple Celestials