Jiang Li was like a bargaining chip. Whichever side he was on, the scales of victory would tip in their favor. Without Jiang Li, there was no doubt the final outcome would have been the First Emperor being controlled by the two Heavenly Daos.
Jiang Li's appearance completely overturned the result. Be it the Immortal Realm or the Heavenly Dao, neither was a problem before Jiang Li. When the First Emperor learned that the Divine Envoy Duye had long been killed, he went on a great slaughter in the Immortal Realm to vent his fury.
Beneath the First Emperor's halberd, Heavenly Immortals and Golden Immortals were no different from mortals, unable to resist. Some Immortals wanted to resist and die with some backbone, but how could Immortals endure the First Emperor's cruel methods? Seeing the miserable state of their companions, worse than death, the other Immortals could only stretch out their necks to be slaughtered.
At least that way, death was swift. The Desolation Halberd was dripping with blood, stained with the blood of Immortals. It would not be an exaggeration to call it the most ferocious weapon of all time.