A Sudden Twist! The Forbidden Steel Rider!

Houtaro and the others are overjoyed to receive a letter from Minato saying that he will take down Geryon. They immediately rush to the location Minato has designated, but suddenly a new Malgam appears. Houtaro is deprived of all his cards except for Steamliner. He is unable to transform into Gotchard. Houtaro still wants his cards back, so he consults with Kyoka and learns that there is only one way to transform, though it is a forbidden technique...