I Became a Necromancer, but Accidentally Turned into an NPC

In a world home to more civilizations and species, the destructive power of their weapons was so immense that every race suffered devastating losses of varying degrees a thousand years ago. To minimize further damage, the civilizations and species ultimately chose to transmigrate into the game world of a previous civilization, turning war into a “peaceful” contest. By growing stronger in the game, they could strengthen their own civilizations. Whether a civilization prospered or declined had become entirely bound to the strength of its people in the game.