As Zeng recuperates, he receives a challenge from the Five-Element Ninjas. Suspecting a trap, he keeps two of his best students, Sheng and Tian Hao, at the school to guard it against an invasion and sends ten others to do battle. As Sheng and Hao help to reinforce the school's defenses and set traps, the ninjas use trickery and guerrilla warfare to defeat their opponents. Hong is overjoyed, but the leader of the ninja, Cheng Yun Mudou, advises that they push their advantage to destroy Zeng's school. Hong agrees, and Mudou sends a female spy, Senji, to infiltrate the school. Sheng convinces a reluctant Hao to take her in after they save her from being beaten.