Ultraman Ginga.

All of the Ultraman and monsters have been turned into figures known as Spark Dolls and become scattered throughout the universe. A young man named Hikaru Raido finds an item called the Ginga Spark which not only allows him to become Ultraman Ginga but also allows him to go UltLive with the figures to revert them to their rightful size and become one with them. Hikaru fights with his friends to uncover the darkness behind the Spark Dolls. Alien Nackie drops a clue that the wielder of darkness resides in their very elementary school.