C1869 This Is the Door of Death!

Only, Tang Ao realized that it was relatively easy to find these array flags from the front, but as more time passed, Tang Ao realized that it was getting harder to pinpoint the location of these array flags. It took Tang Ao an entire two hours to put down the eighteenth array flag in his hand. One must know that Tang Ao had only used seventeen array flags in front of him for such a long time