Unbeknownst to Lia, Raon had altered the natural formation since he had placed all information related to it, Lia and Altair, at the bare minimum requirement of the soul, so that he would be able to alter their destiny as soon as he regressed.
He altered the formation a little bit too much for his level, using his own blood as a medium to guarantee that the previous life's incident didn't reoccur with Altair, keeping her safe.
The formation itself was meeting all of Altair's energy needs with the spirit stones Raon had dumped into it, along with keeping her bodily condition at its peak.
In his previous life, Raon had tweaked the formation to keep Altair in a perpetual dreaming state as long as possible, and it was evident how it only broke when the formation itself had blasted apart.