Nightmare is a monster under of the order of Hexuba sent into her nightmare world to destroy the Galaxy Rangers, who were trapped within after smelling enchanted bouquets of flowers delivered to their quarters from Hexuba's Mansion. After taking a hit from Damon, Nightmare grew giant and the Rangers called upon the Galaxy Megazord to fight him. Nightmare was too much for them so Damon called upon the Centaurus Megazord to help. The Centaurus Megazord beat up Nightmare, allowing the Galaxy Megazord to destroy him.