The episode begins showing Keroro building some Gundam models on Earth but he gets a strange feeling something is going to happen because the narrator ended his sentence with de gozasoro which involves the word sengoku ( which means warring states). Suddenly, a message counter falls on him squishing flat. It turns out the mesage is from headquarters saying that the platoon must travel to planet Sengoku to retrieve the legandary keronian artifacts of war and defeat the warrior vipers there. When they got there, the platoon was shot with a ray gun which made them warrior type outfits and gear and they became known as The Musha Kero Shoutai. ( The Warrior Kero Platoon ) The rest of the platoon sets out to O-Mois restaurant while Dororo went out to find more information about their mission. O-Mois soon takes Keroro, Tamama and Giroro to their first destination while Kururu stayed back at the shop to gather more information while eating a curry covered rice ball. At the first destination, Keroro runs into a boy that looks like Fuyuki but his real name is Fuyukichi. Fuyukichi confuses the platoon for legendary heroes that saved the planet many years ago. But to stay undercover, Keroro lies and says tha they are the legendary heroes so that they could get the treasure. Later that night, the gang goes off to find the treasure but it is nowhere to be found. When they get back to the village, they see it being burned by one of the Warrior Viper brothers. After a crucial battle, Keroro end up stuck in a hole and about to get blasted to bits by the Warrior Viper's cannon but it is interupted by a green glowing object in the distance which turns out to be the first war artifact. Keroro soon grabs the artifact and it turns into a green light saber in the form of a dragon and he defeats the first warrior viper sibling and sends him flying into the stars. Soon, the weapon turns back into its crystal form. In the morning, all seems well and Dororo appears to tell the platoon about the legend of the artifacts. Suddenly, another counter lands on Keroro and it wishes the platoon good luck on finding the other 4 weapons. Dororo informs the team that the next artifact is at a comedy contest and they can't go back to Pekopon until they find all the weapons and the team sets off to the next location.