Start of the War
That night, a whole battalion was evacuated from their quarters so that Sam can carry on the bloodline refinement.
The deal he made with the White-winged Vulture is similar to the one he made with the shadow mice and the queen termite.
The bloodline improvement and a better environment compared to their current ones.
But the power level of him and the Vulture are too far apart, so it would be difficult to for him to completely refine the bloodline, so what he made a deal that he would do a partial refinement and he is doing so now.
The situation of the Vulture is similar to Sky. So, all need is an adequate amount of spiritual energy, but Sam cannot lay down a formation of that type that would be suitable for a Level 6 beast with his current cultivation level.