Nova, also known as Nova 001alpha Eternya, is Ian's psychotic duplicate, created to contain all of the instable mental energy. When Ian found a way to fully clear his mind of all unstable mental energy, he did, and he caused all of that mental energy to cling together like a magnet, before it turned into the being called Nova. However, this form of Nova, while sentient, still remained a part of Ian's mind. But when the events of the Solar Split occurred, Ian-Nova was accidentally torn in half, thus forcing Nova to crystallize and become the nearly perfect twin of what remained, namely Ian.
Nova, while at first may seem real, is in fact just pure mental energy, in the exact shape of Ian, so they are mostly identical. Here is the main difference: Ian is mainly unharmed by most Psychic attacks, and only VERY powerful attacks can actually harm him. Nova, however, is extremely vulnerable to Psychic powers, so vulnerable that a mid-level Psychic attack can almost KO him, if not knock him out straight away, because he is pure, albeit instable, psychic energy. Also, Ian is real, and Nova is... Not. And if Ian decides to fuse with Nova, their personalities, memories, skills, etc., will all combine, thus completing IaNova* once again.
- IaNova is the full name of the real, fused form of Ian and Nova, it is a play on their names, which, if written without spaces, spells IanNova. Remove one of each double letter, and you get IaNova, which is pronounced as the last I and A of the word physica, followed up by the word Nova, as pronounced in the word Supernova.
Nova is pretty much the same as Ian, save for the personality and the eye color. Ian has crimson eyes while Nova has purple eyes, which are kind of like Ian's eyes when he uses psychic attacks, so a pure psychic purple color, only three shades darker. Nova's clothes also consist of mostly black, contrasting Ian's white.