Exponential Boost.

He chuckled evil as he considered it. "When the void universe ends, they too will be inconsequential. Our greatest enemy will be the void universe itself."

"The void universe is the source of their strength. But that will change when it becomes the source of our strength. They too will have to submit."

He was full of anticipation as turned his attention back to the matter at hand. 

The subjugation of the first sage has not only granted them power, it has also granted them useful information such as the location of cosmic sources. 

Now they don't have to look for Cosmic sources themselves. The other clones paused whatever they were doing to go hunt for Cosmic Sources immediately. 

Unlike the first sage, they don't need an Apocalypse weapon to subdue a Cosmic Source. They also don't need an elaborate scheme to take down one. If they can already fight Usurpers, then they can handle Cosmic Sources.