Superhero:
Friedrich Nietzsche
When reading Nietzsche's work, it's best in small doses. He questions EVERYTHING, and for this reason alone I think of him as a superhero.
Nietzsche noted that philosophy and morals go hand in hand. Although it is thought that morality follows some Absolute Truth and is written in stone, morals change historically and change from culture to culture, thereby abolishing the notion of Absolute Truth.
Nietzsche also saw a dichotomy in man. The split was of the Primary man, Dionysus, and the civilized man, Apollo. Dionysus represents music and intoxication as the means to an end, mystical collective ecstasy. Apollo represents an insistence on form, visual beauty, rational thinking and self-control. Obviously Nietzsche was torn between the two.
He was very influenced by Schopenhauer's "Will to live," but in an attempt to change his own life, he tweaked it a little and came up with "Will to Power."
Nietzsche is well known for the infamous quote, "God is Dead." This lead to new thoughts and eventually he coined the term Ubermensch, which is a man without any given meaning.
He thought that man, as a race, is merely a bridge between animals and the overman (another term for Ubermensch). In the future the overman will create his own life and recognize his own power to create. Finding one's own way, embracing and celebrating mistakes, realizing self-knowledge and creation is a process to be enjoyed.
Along this same vein, Nietzsche warns of the Master-and-Slave morality. We either create our own values and morals or we follow and observe the values and morals of others.
Nietzsche has left us with many ideas and concepts, my favorite being "Eternal Recurrence," but I'm not going to beat a dead horse with that one.