Franklin’s powers allowed him to create the universe, dimensions, avoid mind control, and every other cool power you can think of. Franklin Richards is considered a Beyond Omega Level mutant, and he is the only one in that category, making him the most powerful mutant on Earth.

As the rest of the Fantastic Four mourn her, Reed puts their son on her chest to say goodbye, and then he miraculously resuscitates her. The parents spend most of the movie worried that Franklin might be some kind of monster like Galactus,

In a 1982 arc by John Byrne, Franklin gets frustrated trying to solve a Rubik’s Cube and uses his powers to age himself into an adult body, though he couldn’t actually gain more emotional maturity. He winds up going back to being a kid, placing restrictions on his own abilities to allow him to have something of a normal childhood.

First Steps introduces plenty of characters to the MCU, but its strongest one isn't Galactus or Franklin Richards.

In Marvel Comics, Doom’s fixation on Franklin is legendary. He views the boy’s near-limitless powers as the key to creating and ruling Battleworld, a twisted reality of his own making as seen in Secret Wars.