Sixth-Tier Magic Artifact

Watching the aura of the Slay Immortal Sword Formation surge, Bi Changsheng nodded lightly.

However, Bi Changsheng did not stop what he was doing, because he had not yet finished upgrading the Slay Immortal Sword Formation.

With a wave of Bi Changsheng's hand, Slay Immortal, Slay Immortal, Trap Immortal, and Absolute Immortal—the four Magic Swords—flew straight out of the Slay Immortal Sword Formation and finally arrived before Bi Changsheng.

As one of the cores of the Slay Immortal Sword Formation, the Immortal Slaying Four Swords had originally been a major force in amplifying the formation's power. Now that the formation had been upgraded, however, they were somewhat unable to keep up with its pace.

After years of tempering, the Immortal Slaying Four Swords had already grown to the limit of fifth-tier magic artifacts.

Now, Bi Changsheng wanted to advance the Immortal Slaying Four Swords into sixth-tier magic artifacts, thereby enhancing the power of the Slay Immortal Sword Formation once more.

Thus, Bi Changsheng directly activated the Sacrifice Refining Method. After a vast amount of his lifespan burned within his body, it transformed into energy that nourished the Immortal Slaying Four Swords.

Very soon, the Immortal Slaying Four Swords broke through the limit of the fifth tier. However, for them to advance into sixth-tier magic artifacts, the most important step still remained.

With a thought from Bi Changsheng, the Chaos Great Dao surfaced around his body.

After this period of comprehension, Bi Changsheng had already comprehended the Chaos Great Dao to the two-tenths stage.

Although Bi Changsheng had only raised his comprehension of the Chaos Great Dao by one-tenth after breaking through to the Human Immortal realm, this progress was already extraordinarily fast.

One had to know that other Human Immortal cultivators often needed decades or even centuries to improve their