Iron Spider Mask lead a siege of an EAGLE lab which contained the "Yougen Germ" within it; this germ works similar to a flesh-eating bacteria, burning the skin and eating away at the body until nothing but bone remains. His intent was to use the germ with his spiders to attack people and kill them instantly with their bite. When the Yougen Germ is stolen, Kaijo immediately takes the blame for the defeat due to stopping to meet with children as Peggy is forced to stop the invasion on her own leading to the Masked Monster's victory; this leads to Akarenger disappearing until he discovers a way to stop him.