The reason so many human spirits had come forward was because Wu Jiu had promised one condition, that all human spirits who participated in the construction of the Serene Spirit Tower would enjoy priority access into the tower to cultivate after the Serene Spirit Tower's construction was completed.
Because of the addictive allure to the Serene Spirit Tower, it drew many human spirits to come rushing forward for conscription. The number was so immense that all the avenues leading towards the outside of the Serene Spirit Tower were filled to almost overflowing.