The sword formation on the seventh level of the Copper Mirror is called the [Great Sun Evil Extermination Eight Directions Sword Formation], a mountain protection array used by the Heavenly Sword Sect to suppress the Great Sun Sword Tomb.
Although the Great Sun Sword Tomb houses thousands of Sword Ghosts, it does not mean it cannot lose control.
The Death Tomb was caused by the Sword Tomb losing control, an intricate small world composed of countless taboos, even Land Immortals find it hard to handle.
To the Heavenly Sword Sect, the Night Patrol Deity losing control is inconsequential.
The key is to not affect the Great Sun Sword Tomb, so the mountain protection array did not participate in subduing the Night Patrol Deity, instead covering the seventh level of the Copper Mirror to prevent deceitful objects from entering deeper.
