Estranged son of the evil mutant Mystique, Kurt Wagner was raised by a fortune teller and grew up as part of a travelling circus in Germany. Using his unique physique and agility, he performed as the star acrobat for years until finally attempting escape. During this escape, Nightcrawler teleported for the first time, an event that lead to him being rescued from an angry mob by Professor Charles Xavier, who came to recruit him into the X-Men.
After rescuing a de-aged Storm from the Shadow King, Gambit was brought back to the X-Mansion where he eventually joined the X-Men. As a mutant, Gambit possesses the ability to convert the potential energy in an object into destructive kinetic energy. Gambit utilizes this power mostly in the form of throwing kinetically charged playing cards which explode on impact, or by super charging his extendable bo staff.
Gambit and his fellow X-Man Rogue have an unsteady relationship, with a nearly equal mix of time together and time apart.
Jean Grey manifested her mutant psychic abilities at an early age, and was subsequently sent to the Xavier School for Gifted Youngsters to learn control over her powers.
As a founding member of the X-Men, she's spent most of her life as a hero and has the calm confidence of a seasoned pro.
When Jean served as an avatar for the Phoenix Force, an immensely powerful entity of death and rebirth, her powers were greatly enhanced. Although she no longer operates on that scale, her telepathic and telekinetic abilities make her a formidable opponent.