Taizan has one of his subordinates, Murasame (Shikigami - Shirogane no Chiyorozu), set a trap for Riku, saying that his parents have been found in the Fukumaden.
The trap was meant to make Riku lose his fighting spirit, but it actually made Riku so angry that he uses the Daikoujin and has Kogenta destroy everything in the Fukumaden.