The cause of the conflict was the surviving Thunder Dragons of the monster rampage originating in Fitun's 'Labyrinth of Trials'... the Dungeon that was now known as 'Garess's Ancient Battleground.' They were the ones who had sensed that Vandalieu was the 'Dragon Emperor' and the 'Demon King,' awakened from the monster-inherent instinct that told them to seek out battle, and fled in obedience to the survival instinct ringing alarm bells in their minds. Thus, they had been tamed by Vandalieu without being turned into Dragon Zombies, then teleported here from the city of Morksi.