The True Scarlet Sky!
From the very moment the army of monsters jumped out of the cracks, no one could afford to care about the battle in the sky. Only those on the back could observe every now and then, but that didn't really matter for the Heavenly Demon.
Although the monster army was a blatant threat, it could never compare to the danger imposed by a Demon Lord. They were still just monsters like any others that possessed the authority of spatial invasion, the ability to open cracks to other worlds! However, not anyone received that authority just like that!
Only by destroying all competition could a monster claim the Demon Lord's throne. Once they became unrivaled, they would be bestowed the ability befitting of that title, bringing misery to countless worlds like locusts that consumed everything on their path.
Knowing that full well, the Heavenly Demon couldn't hold back anything. While he started up using his fists, it was time to use his own authority as a Guardian.