「ギャーソリンがご入用なら、この調達屋にお任せを」 度重なる敗北に業を煮やしたキャノンボーグは新兵器を開発。 開発の天才である大也が開発したブンブンジャーのシステムをトレースして作られた新兵器は強大な敵として立ちはだかる。 しかし大也たちはそんなことは露知らず、 キャノンボーグの作戦通りサンシーターの攻撃を被弾。 爆上げが合言葉であるブンブンジャーの面々は どういうわけか“爆下げ”になってしまった…！！ ─と、万事休すかと思われた惨状でふと姿を消した玄蕃。 彼はサンシーターに寝返り 調達屋の仕事を再開していた──。
``If you need Gyasolin, leave it to this procurer.'' Cannonborg, frustrated by his repeated defeats, develops a new weapon. A new weapon created by tracing the Bun Bunger system developed by Daiya, a development genius, stands as a powerful enemy. However, Daiya and his friends were unaware of this and were hit by Sunseeter's attack as per Cannonborg's strategy. For some reason, the members of Bunbunjar, whose password is ``bakuage'', have become ``bakugoe''...! ! ─And Genba, who suddenly disappeared in a tragic situation that seemed like everything was going to end. He switched to Sunseeter and resumed his job as a procurer.
