Alex calculated the number of Array Plates he needed to trap everyone from Black Devil Sect. He could somehow trap a thousand people with a single Rank 7 Barrier, but the problem was how they split their group into five with four five-hundred squadrons and one thousand people in the headquarters.
He needed five barrier arrays to trap one group or three thousand people in total, and he fought with five groups. In other words, he needed to make twenty-five Array Plates for this operation. Of course, he couldn't forget about the Gathering Array to power up this Array Plates so they could stay for at least an hour.
Alex made a total of fifty Array Plates in a single day. It was quite an achievement, only for those with a strong soul like him.
Although it was a bit costly either for the monster blood or Spirit Gems, they needed to speed up this process.