This was “Using softness to overcome hardness”, which was another variant of the “Dripping water pierces stone”method in the “Infinite way of the sword”.
In plain English, it was “Rebounding”.
The sword Qi itself did not possess lethality, but it was more of a fusion of the Taiji way.
Through the sword Qi, one could alter the circulation of the surrounding airflow, thus causing the flying objects that were ramming towards them to change their original trajectories.
Such a sword technique could be used skillfully when Yi Jianchuan was a true immortal. Now that it was being used, it was naturally easier for him to use his hands.