When he was speaking with the twins, learning every detail about tribulations he could, he learned something interesting: the heavens decided the complexity of your tribulation based on the energy cultivation of the one triggering it. This meant that even if the power of his tribulation scaled to a dao formation expert times the nine of them here, it would be created with saint level energy and comprehension.
The reason Dyon found this point to be worth risking his life over was because his undead body was restricted by only two things: his stamina and comprehension.
