The island had a diameter of around a hundred kilometers. From afar, Zhang Xuan could see that it was filled with all kinds of towering plants, granting it a lush appearance. Surrounded by a massive formation, the spiritual energy within was particularly concentrated, and from time to time, one could see formidable saint beasts dancing in the air above.
"To be able to conceal an island with a diameter of a hundred kilometers, the man who set up the formation must be at least a 7-star formation master!" Zhang Xuan noted in astonishment.
He was currently a 6-star pinnacle formation master, but even so, a formation of such scale was still far beyond his means. Just how powerful must the senior who had built the Poison Hall here be?