Illusion of Gaia

Will stumbles into a "Dark Space" where he meets a strange being called Gaia. Gaia tells Will that he must leave his home and save the world from a coming evil. A comet is approaching, and it will bring ill fortune to the world. As he travels, Will gains the ability to change into other forms, each with special powers: Freedan, a dark knight, and Shadow, a solid form of energy. (Wikipedia)