A Great Battle of Ten Thousand Races? This Venerable One Rides into Battle on a Coffin

Transmigrating Back, I'll Take Earth to the Skies!" "Back from Transmigration, I'll Crush the Myriad Races!" “Earth! This venerable one has finally returned!” “What? Only three years have passed, and the myriad races have invaded, leaving everything in chaos? Isn't this the perfect chance for me to merge back into humanity?” “Foreign races reign supreme, while humanity is insignificant? No way. When I left, humans were the rulers!” Good news: The Demonic Path Patriarch has transmigrated back to Earth, riding in on a coffin! Bad news: Less than a tenth of his power remains, and all he has left is his coffin. To make matters worse, the despicable myriad races are grinding humanity into the dirt!