Head: Cast (Trigate/Slayer) Star Trek Picard
Torso/Arms: Destro/Prof. X Buck
Legs: Comic Pack Shipwreck (trust me)
Cerebro Helmet: Mon Mothma?

I never really told the Professor X story in my main EXCAL continuity, but it lined up with when I first started making figures with more comic styled powers. The Professor had been recruited to EXCAL at about the same time that Tony Stark defected from SHIELD. The story had some mild Civil War undertones to it, as SHIELD was promoting Captain Rogers to lead the organization, pitting him against Stark.

Realizing there was a whole bunch of undiscovered powered people out there, EXCAL brought Xavier on board with the hopes of finding and recruiting them for the fight against world tyranny. The hope was to get them before SHIELD, but more importantly before MEDUSA, which had tapped its own mutant leader known as Magneto.