Genghis was the First Demon God, the oldest and most ancient of the demons. As long as it existed, other demons would live a long life. Its death would greatly weaken the demons.
During a fight with Genghis, there must be no movements such as jumping, flying or any actions that would cause one to leave the ground, this also applied to pets. As such, Li Yi did not summon Dolly to assist in combat.
Genghis would release a black noxious smog which would cover the entire hall once any feet were off the ground, reducing HP by at least 100,000 per second until the battle was over.
It was better to get hit than to leap away from the ground. This was the most basic rule for tackling Genghis.
Li Yi's movement speed was fast enough, but he would still take damage from time to time. A shot from Genghis would cost between 30,000 to 50,000 HP, even his high HP would not last long.