Complex sentence: Danny, who calls himself'Danny Phantom' in ghost form, develops the ability to fly, become invisible, and turn his body intangible at first and throughout the timespan of the series learns other powers such as his ghost ray, ghostly wail and cryokinesis.
Split into simpler sentences: Danny, who calls himself'Danny Phantom' in ghost form, quickly develops the ability to fly and become invisible or intangible. Over time he learns other powers such as his ghost ray, ghostly wail and cryokinesis.