When Amon came to the Northwest border for his mission, he planned to obtain the cooperation of the warlords currently fighting the Cryanid Plague. He figured that if he was to investigate the reason behind the Cryanid's drive to invade the Mercy Faction, he would have no choice but to venture beyond the border.
From the tales he had heard about the misty border, it was not a place someone ventured into alone. While he had a hidden puppet army, or even if he had the luck of sneaking through the misty border without being preyed upon by powerful spirit beasts, he still had the Cryanid army to deal with. To investigate the Cryanids inside their nests, he would need an army filled with powerful cultivators just to survive.
However, a second option revealed itself during the battle outside Defunct Edge City. This option appeared when he heard the humanoid Cryanid speak human language. If a creature could be communicated with, then it could be bargained with.
