Jou wants to become a Boonboomger, but Taiya rejects him, saying he doesn't have what it takes just yet.

Genba has his first solo delivery job for the ISA. Worried about him, Mira decides to tag along, when the Sanseater attack the duo.

Jou finds a monster created by the Hashiryan who refuses to attack humans and befriends him, determined to protect his new friend from the enemy.

Summer! Camping! Tent Grumer!? Tent Grumer interferes with children who are enjoying camping in the mountains. Then, Taiya and the others challenge the newly born "Boonboom Leon" to a battle!

The Sanseater try to make Mad Rex recover his memories.