Upgrading Demon Suppressing City to Tier Three took nearly half a day. Upgrading it to Tier Four or even Tier Five was not something Huang Yu could accomplish instantly just because he had money and resources.
However, seeing the sturdy city rise from the ground in such a short time, and the ten thousand warriors and one thousand Spellcasters gathered inside Demon Suppressing City through the teleportation passage, everyone immediately felt much safer.
Limited by the size of the Tier Three Demon Suppressing City, ten thousand troops and one thousand Spellcasters were already the maximum it could currently accommodate.
However, Huang Yu had already paid the Soul Crystals and resources needed to upgrade Demon Suppressing City.
Once the teleportation passage disappeared, Demon Suppressing City would be upgraded into a Tier Four city, fully capable of accommodating the sixty thousand troops advancing into the Abyss.
Furthermore, the exit of the teleportation passage was still located inside Demon Suppressing City. When the city's defenders ran low on stamina, they could switch out with the troops in Huanyu City's training grounds through the teleportation passage at any time.
Huang Yu knew that what awaited them next would be a long, arduous, and brutal war of attrition.
Without paying a certain price, Huanyu Territory could not possibly establish a foothold in the Abyss.
Especially during the period after the teleportation passage disappeared but before Demon Suppressing City was upgraded to Tier Five.
Even if Huang Yu raced against time and upgraded Demon Suppressing City at any cost, that period would still last more than a day.
Without personnel rotation and with no unlimited Teleportation Quota, the Huanyu Army would have to fight at high intensity at all times against the endless monsters and Demon Army.
However, once Demon Suppressing City was upgraded to Tier