Noah didn't know much about the Second Life formation. He had learnt a bit about its functioning and requirements from Andrew Elbas, but even the Royals couldn't be sure about every detail.
After all, that was a legendary formation that those Mortal Lands didn't see for millennia. The records concerning it were bound to be imprecise and fragmented.
Still, even that little information gave Noah an idea. The Second Life formation would activate only after a cultivator's death, which meant that he could seize anything he wanted from his opponents before that moment.
In theory, Noah could eat the dantian of his opponent before killing him. Even a miraculous formation couldn't affect his meal once the "Breath" inside that center of power became primary energy for his body.