奮闘むなしく、ランナープリズンに囚われてしまったリュウセイ達。仮面の男は満を持して自らのガンプラ、ガンダムバルバタウロスを召喚する。圧倒的な力でバトルフィールドを蹂躙する悪魔の機体を前に、３人は絶体絶命のピンチを迎えてしまう。
After a hopeless struggle, Ryusei and the others have been captured by the Runner Prison. Now the masked man finally summons his own Gunpla, the Gundam Barbataurus. His three opponents are in desperate peril as they face this demonic machine that tramples the battlefield with overwhelming power.
