Solution

On the left path, ignore the statues and the katana case, then defeat Moko the Restless.

Description

Long ago, in the days when war and strife plagued Hingashi, there lived a man who built his legacy upon a mountain of enemy corpses. Fiercer than a mad tiger, Moko the Restless emerged victorious from every skirmish─but his might would be his undoing.

Fearing that the warrior would rebel against him, Moko's liege lord ordered him slain in the dead of night. The deed was carried out with Moko's own blade, which, having cleanly severed its master's head, soon began to burn red. None could say whether this crimson aura was begat by the warrior's lingering fury or the ire of his victims, but it resisted all efforts to remove it. In a last, desperate attempt to purify the sword, the lord's servants carried it to a sacred peak and plunged it into the holy waters...only for the weapon to devour the font's spiritual energies. From that moment on, any soul who attempted to wield the blade was consumed by murderous rage.

Tokimori claimed that the holy waters in the tale might be found on Mount Rokkon itself, where a lake of particular spiritual power lies concealed. A small shrine allegedly graces its banks, and I cannot help but wonder if treasure hides within. Unfortunately, the path is a closely guarded secret known only to the highest-ranking monks, so we are left to fumble in the dark.