What is it about Superheroes that never gets old? Is it the neverending quest to defeat evil or satisfy the narcissistic attitude of being more than they really are? Some of these superheroes are listed as being protagonists but careful thought reveals that they are an ideal rather then real symbols for leadership. Much like Batman and Bruce Wayne who are the same person but live totally different lives is one perfect example of the real-life superhero. Then again, they come in all sizes and shapes. Some can use mental powers, while others get it by default. Superman is clearly an example of an alien who is nobody from his home planet, but on Earth -he's different. It changes him forever at that point.
Software companies love the Superhero themes since everyone has a favorite that they remember as a kid. Playtech and Cryptologic both cover the Marvel and DC comics. Wagerworks (IGT) also gets a stead flow of comic characters also. Even Microgaming is getting some of the darker more sinister Dark Horse characters. There is no end to the variety of superheroes as we know it since society surely could use some these days.