MegaGhost (MegaGhost #1)

Can life get any weirder for junior occultist Martin Magus? Living in the haunted city of Dunwich Heights is strange enough for a kid investigating the unknown, but when he comes into possession of a bewitched ring, he discovers that he now has the power to summon Megaghost, a giant supernatural robot sworn to defend the world against the creepy things that go smash in the night!