Souten no Ken Regenesis Episode 5, The Grudge of the Starving Wolf (餓狼の怨念)

Official synopsis In the Shanghai concession, the Chinese government army rains down bombs: war finally breaks out. Pan's mansion also becomes a target of the bombings. In the cathedral spared by the strikes, Kenshiro learns from Erika that Fei-Yan has not returned since the previous evening. "The god of the Yuezhi will not forgive Hokuto!" Standing before Fei-Yan is Yasaka, who wields the Seito Getsuken. To wash away two thousand years of resentment accumulated by the Seito, he frees Fei-Yan whom he had captured, and engages in combat. At the end of a fierce struggle, Fei-Yan discovers the ultimate secret of the Seito Getsuken unleashed by Yasaka. "Are you... you...!" Fei-Yan's voice echoes through the ruins.