Marvel: I Became Superman by Basking in the Sun

Tony Stark is kidnapped in Afghanistan, facing certain death. His adopted brother, Leon, is seemingly helpless, stuck orbiting Earth. For eighteen years, Leon, a transmigrator, endured the dangerous Marvel universe as an ordinary man. But everything changed on his 18th birthday. After six months of relentless sun exposure in space, he awakened a power that redefined 'invincible.' With a Kryptonian physique, capable of flight, unimaginable strength, and heat vision that melts steel, Leon rips through space to crash-land. He single-handedly dismantles an entire terrorist base, plucks shrapnel from Tony's chest with casual ease, and obliterates the mountain with a glance. Tony thinks he's safe, but Leon has only just begun. The world isn't ready for a Stark with god-like power, and the only question is: will he be its protector, or its silent, terrifying master?"