Even if ten thousand Demon Spirits were to form a circle, their density alone could create a gigantic sphere hundreds of meters across.
Simply slashing at the ones within arm's reach, managing to kill dozens in an instant with ten thousand swords would be considered quite good.
Thus, Lin Xin knew that most of his strength was being used to repel the Demon Spirits, to gain opportunities to catch his breath and switch tactics.
Moreover, most of the time, he was actually responding to the assaults launched by the army of Demon Spirits. The immense tail of the Elephant Trunk Turtle, the sharp claws of small Void creatures, and the dark qi occasionally emitted by dragon-headed beings.
In the swings of his sword, the majority were for defense.
Most of the actual slaughter was carried out using the large-scale Purifying Fire or by extending and sweeping Sword Light.