Kouchuu Ouja Mushiking Super Battle Movie: Yami no Kaizou Kouchuu

Sujibuto arrives in the forest eager to challenge Mushiking, but their contest is interrupted when Ricky attacks under the dark fairy Adder's control and carries Mushiking away. Popo and his companions head into the enemy's hideout to rescue their friend.

Inside, they discover a threat beyond the controlled beetles they already know: Adder is preparing an enormous beetle altered by dark power. Their rescue mission becomes a struggle to keep the entire forest from falling under his rule.