What Aatrox was using his previous lore and why the new one pales in comparison.

"The earliest tale of Aatrox is as old as recorded history. It tells of a war between two great factions remembered only as the Protectorate and the Magelords. Over time, the Magelords won a series of crushing victories, leaving them on the brink of obliterating their sworn enemy forever. On the day of their final confrontation, the Protectorate army found themselves outnumbered, exhausted, and poorly equipped. They braced for inevitable defeat. "

Ok, so the Protectorate and the Magelords are apparently these two factions that actually fought on the Summoner's Rift. You can see a tome or something on the wall of Top lane that depicts their struggle. This also solidifies Aatrox as someone older than recorded history.

*"Just when all hope seemed lost, Aatrox appeared among the ranks of the Protectorate. With but a few words, he urged the soldiers to fight to the last before throwing himself into battle. His presence inspired the desperate warriors. At first, they could only watch in awe as this unknown hero cleaved through their enemies, his body and blade moving in unison as if one being. Soon, the warriors found themselves imbued with a potent thirst for battle. They followed Aatrox into the fray, each fighting with the furious strength of ten until they had won a most unlikely victory. *

You see, this guy is not some puppetmaster or some coward that pulls strings behind the scenes as i've seen numerous Boards members say. They have clearly not read his lore before the retcon and they think they have the right to make assumptions based only on his VO without understanding it.

"Aatrox vanished after that battle, but the Protectorate army's newfound fury did not. Their surprising triumph led to many more until they were able to finally return home victorious. Their countrymen hailed them as heroes, but though they had saved their entire civilization from destruction, darkness lingered in the mind of each warrior. Something within them had changed. Over time, their memories of battle faded, only to be replaced with a grim revelation: their acts of heroism were, in fact, brutal atrocities committed by their own hands. "

THIS! This is why Aatrox's influence is borderline terrifying. Imagine you're attacking the enemy but you forget yourself in the battle because of what someone like Aatrox has imprinted on you from his image. You lose yourself in the fighting. Aatrox reveals the monsters within men as they devastate entire armies with their pure rage and viciousness. The men return home and as their minds clear, they realize they went beyond that but don't remember themselves doing it. They weren't themselves..or were they? Homes burning, unarmed civilians being slaughtered, families being put to the sword and the stench of bodies....they would enjoy that...and so, they had witnessed the reason why Aatrox was there. The truth.

We're all monsters.

"Tales like these appear among the myths of many cultures. If they are all to be believed, Aatrox's presence has changed the course of some of the most important wars in history. Though these stories remember him as a savior in dark times, Aatrox's true legacy may be a world filled with conflict and strife. "

His purpose was his legacy. To change the course of history so war could scorch the land and the skies throughout history. To stand atop countless bodies as the true artisan of war as his subjects are exposed to the unaltered, unadulturated truth of what lies within...a truth they would reveal to themselves through their actions in battle without the possibility for denial because they did it. They are the authors of the horror stories others would tell later.

That is a whole new level of cruelty.