Sanzu River
In "The Master Returns," Master Xandred learns of Serrator's secret plans and goes to Earth to deal with him. When Serrator is taking too long to get back to Dayu on repairing her Harmonium, she ends up confronting him which leads to an altercation where Serrator defeats Dayu. Luckily for Dayu, Master Xandred arrives and repairs Dayu's Harmonium upon reclaiming it from Serrator who flees. When Master Xandred is placed in the depths of the Sanzu River to recuperate, Serrator takes over his ship with no opposition.