The Heart Void Sword Technique and the Spiritual Sword Technique were both created by Su Xin, but the two are completely different.

The Spiritual Sword Technique, based on spirituality and swordsmanship, centers on the rule of destruction.

It focuses all power on the sword tip, unleashing it in an instant to pierce through everything.

However, the Heart Void Sword Technique centers on the rule of space, with swordsmanship containing 'space slicing', unleashing the strongest slicing and tearing force in an instant.