Kuo's tenure in Tang Dynasty would not last long. The guitarist left the band in May 1999 following an argument with Ding Wu over the bombing of the Chinese embassy in Belgrade. Kuo also cited frequent clashes with Ding's then-girlfriend in what he called a "Yoko Ono situation" as another impetus to quit. He was briefly replaced by Iron Kite frontman Yu Yang, who would in turn be replaced by guitarist Chen Lei. Kuo would go on to establish a folk metal band called Spring and Autumn (), which released one album in 2006.