With cultivators, it was not wrong to say some could be as powerful as an army but that was in the short term. To put it another way, cultivators could sprint their output to the point a whole army could die if nothing could stop them.
However, the world was not a vacuum. Cultivators existing in all walks of life meant simple power was not enough. It was also required to pace the expenditure of Qi. When actually waging war, an army was far more powerful than any single individual subduing an actual nation.
Gravis rejoiced at his Emperor's words and began to send out his forces in earnest across the lower world as Keera reigned in her demons above. They coordinated as the battles changed.
"Divisions 1 to 3, focus on rounding up any Sky Realm forces. Division 4 will secure the main structures of Celestia while Division 5 secures the brainwashed citizens." Lind had left explicit instructions to limit the death toll on the controlled citizens.