Fabio Medina is a teenaged
mutant whose powers first appear when he was the victim of an attempted robbery on the streets of San Diego. After manifesting his abilities, the
bouncing balls emanating from his body frighten onlookers, and he is taken into custody by the San Diego Police Department. However,
Cyclops and his group of
X-Men arrive just in time to rescue him. A squad of different-sized
Sentinels attack the new mutant and Cyclops's team, who manage to destroy the Sentinels. Fabio is then invited to join the X-Men when they depart San Diego. Although Fabio is reluctant, he decides to follow them. Fabio then joins the X-Men during their visit to Eva Bell's home and the encounter with the
Avengers, before being dragged into limbo during
Dormammu's attempt to kill them. In the aftermath, Fabio demands to be taken home, where his family questions his disappearance and is befuddled at his claims of being a mutant. When
S.H.I.E.L.D. agent
Alison Blaire (Dazzler) arrives and questions him about Cyclops's location, Fabio loses control of his powers. He is taken into S.H.I.E.L.D. custody but is again rescued by Cyclops' team and rejoins them. He later assists in the battle against the Blockbuster Sentinel by concentrating the emission of his gold balls to topple them. He then assumes the mutant nickname "Goldballs". After many adventures under the guidance of
Illyana Rasputin and
Shadowcat, Goldballs and his teammates express uncertainty about continuing as students anymore. Goldballs next appears in
Spider-Man, where he is seen attending Brooklyn Visions Academy. He becomes the classmate of
Ganke Lee and
Miles Morales, aka the second Spider-Man. During the "
House of X and Powers of X" storyline, Fabio would make his home on the new mutant homeland of
Krakoa where the true nature of his seemingly mundane mutant powers would be revealed. Working in conjunction with
Proteus,
Elixir,
Tempus, and
Hope Summers, he uses them to resurrect Cyclops,
Jean Grey,
M,
Nightcrawler,
Warren Worthington III,
Husk,
Mystique and
Wolverine under
X's instruction. After becoming a member of
The Five, he changes his codename to "Egg". ==Powers and abilities==