Complex sentence: Like his mainstream counterpart, Tony has a drinking problem and life-threatening affliction; in this case an inoperable brain tumor which will kill him anytime between six months and five years, which he explains is the reason he has become a philanthropist and superhero.
Split into simpler sentences: Like his mainstream counterpart, Tony has a drinking problem and life-threatening affliction; in this case an inoperable brain tumor. With a life expectancy anywhere between six months and five years, he choses to become a philanthropist and superhero.