Cannonball

Way in the background of the concept art can be spotted Cannonball, a mutant who possesses the ability to fly at supersonic speeds while encased in an impenetrable force-field. He can do that by generating energy and releasing it through from his skin, to various effects (the most usual ones are flight and force-field). If at first he only released the energy through his feet and arms, he eventually mastered his ability and was able to release it through his entire body.

As seen in the concept art, he is in flight – but, despite the tremendous speed, he has complete control of the maneuverability. He can steer in any direction with easiness just by sheer will (though we can expect that in the movie some other explanation will be provided).

The force field generated usually keeps him out of harm’s way. But Cannonball can also use it in order to protect others or to entrap his enemies. The force field is so powerful that he was able to withstand the planet-shattering blows coming from Gladiator.

This member of the X-Force is also suspected to be a member (or at least descendant) of the Eternals, since he also has the ability to come back to life after being killed.