Eris and the sixth ranked abomination clashed across the whole camp and tens of low-ranked abominations ended up getting killed just from the shockwaves of their fight.
In that fight, Eris managed to comprehend a few things about the abominations. Each rank is ten times stronger than the one before it. The first rank abominations are equal to a level 100 human.
This means that a maxed-out level 1000 human can only stand on equal grounds with a second rank abomination. This had made two things clear for her, the leveling system's true purpose might've been to nurture soldiers to fight against the abominations.
When Eris looked at her own system she realised that it's power was already fading away, melting back into the universe. As a demi-goddess that's about to ascend, she does not need to waste Aria's {The Overgod's Archon who grants the system's power to people.} powers.