The existence of Fierce Beasts was a tool the Dragon God used to anchor time.
The Dragon God did not possess Su Ming's Trinity methods, nor did he even know of the Time River's existence. He merely had a vague understanding of time and a relatively clear concept of the past and future.
He knew that altering history was possible.
Even peering into the future was not impossible.
And when the past and future could both be changed by experts above the God King level, factors that did not change along with history became critically important.
Through the Dragon God's research, Heavenly Tribulation was a force capable of existing across time.
This did not mean that Heavenly Tribulation crossed from the past into the future. Rather, Heavenly Tribulation itself possessed such an ability.
A Heavenly Tribulation from the past would not strike the future for no reason.
Nor would a Heavenly Tribulation from the future strike the present.
The so-called trait of Heavenly Tribulation crossing time meant that, as the entire universe developed, Heavenly Tribulations that should have occurred would not vanish into thin air.
"The Heavenly Tribulations that Fierce Beasts should experience are already established history. Even if history is altered and affects a Fierce Beast's Tribulation Crossing, the Heavenly Tribulation will not simply disappear from history."
This was the Heavenly Tribulation Conservation Law.
Heavenly Tribulations from the past would not continue shifting through history. Instead, they would be transferred into reality.
For example, if a Fierce Beast underwent Heavenly Tribulation a thousand years ago, but history was altered so that it died early, then the history of it undergoing Heavenly Tribulation would disappear along with it. The entire world would correct itself according to the altered history.
During this process of correction, that Heavenly Tribulation would not appear