The cargo inside the warehouse were decreasing by crates and cartons. Each time Zhang Tie appeared, the cargo would be reduced by 400-500 kgs, at least in the warehouse.
With nine wolves' strength in his body, Zhang Tie had super strong endurance and strength. He just kept carrying the cargo from the warehouse into the Castle of Black Iron without even knowing what fatigue was.
Two hours later, a greater part of the cargo in the warehouse had 'disappeared'. Sitting on a box, Zhang Tie started to enter meditation of 'Mental Arithmetic by Abacus' with his legs crossed so as to recover his spiritual energy. Right now, although Zhang Tie felt a bit tired, he still had enough strength to continue. However, after 100-200 times of carrying the heavy boxes into Castle of Black Iron in a short period of time, even with his increased spiritual energy Zhang Tie could still not stand it spiritually.
