A Beast Warrior with two mouths; a larger mouth which opens into a smaller mouth. This smaller mouth spits out a gooey substance that is difficult to remove on it's own, particularly for the Flashman due to a celestial alignment of the five Flash planets interfering with their powers and preventing their Prism Flash from activating. With pieces of their bodies stuck with the substance, the team is forced to flee from it and Wandala until the alignment has ended, upon which it becomes easier to remove the goo with their Flash powers and transform once again. The Gostero takes a bombardment of the five prism weapons until a Rolling Vulcan destroys it; after being rebuilt and grown by Kuragen, it is destroyed by Flash King.