In the myth of Achilles, he is known to be a warrior of immortal status and the greatest fighter in the army of Agememnon, and those of all the Greeks. But the only weakness in which he possesses is what makes him penetrable. That weakness is his heel. The character of Superman is quite similar in this aspect, he is almost an immortal like Achilles and he also has only one weakness that would bring him down. That weakness of his is known as Kryptonite. But both these heroes are immortal due to very different reasons. Achilles is like this because at a very young age, his mother the sea nymph Thetis held him by his heel and dipped him into the River Styx. The only reason why he isn’t completely immortal is because his heel was the spot where his mother held him, and it wasn’t touched by the water. Our modern day hero, Superman has a different story when it comes to his immortality. Superman is a native of the Krypton, where the planet has a red sun that’s under a yellow sun. The cells within his body act as a living solar battery, which absorbs the energy thats generated from the two suns; giving him superhuman powers. While he possesses tremendous strength; it is not infinite and the full extend of his power has never been precisely measured. The Kryptonian native has developed many other superpowers; ranging from his super sharp senses, telescopic/microscopic vision, heat/x-ray vision, superhuman speed, his ability to defy gravity, the power to fly through anything and of course he can generate a force field that surrounds his body thanks to his irradiated cells.