The main reason why Yun Yang did not mind using the two pieces of the secret map as the pawn in his ploy this time around was so that he could attract the sects and schools that were involved in the war between the two empires.
He wanted to annihilate them, in the same manner as he had done to the Ma-i Sect; he fully intended to use the goriest and extreme method to serve as a warning to others.
It was compulsory to achieve a horror of such great extent that no one dared to forget it and no one would dare to try again. Martial world sects and martial artists should mind their own business in the future when two empires were engaged in the hegemony of the world. The fight for dominance among the kingdoms was not something they should get involved in!