Ryan Gosling or Alexander Skarsgård could play Sentry in a rumored Marvel Studios solo project.
Sentry is a powerful hero with an evil alter-ego, the Void.
The King in Black comic event features the awakening of Knull, a god of darkness.
Knull is unlikely to appear in the Marvel Cinematic Universe due to rights issues.
The Thunderbolts team in the comic is led by Kingpin to find and use Sentry's body as a weapon against Knull.
Sentry may be used in the Thunderbolts film, possibly with the team manipulating or convincing him.
One theory suggests Sentry starts on the Thunderbolts' side before turning evil.
Kingpin or Val (played by Julia Louis-Dreyfus) may lead the Thunderbolts team in the film.
The Thunderbolts film has not yet been officially announced by Marvel Studios.