One of the enchanted walls of Otosan Uchi.
Komachi's Travel Guide
In the final assault of Fu Leng’s attack on Otosan Uchi, the remaining forces threw themselves at what seemed to be an undefended wall. In truth, the Kuni had created a trap. They drew the corrupted army in, then enacted the ritual of binding as the enemy crashed into the Western Wall.
Over three hundred of Fu Leng’s legions vanished into the wall, never to be seen again. They remain to this day, trapped inside their tomb at the very heart of the empire. Today, the howls of the goblins, ogres, and oni can still be heard through the streets of the Karada district, and no one lingers near the Western wall any longer than they must.