Fairy Tail System: Erza is My Starting Point

Ian traveled through time, but he didn't panic at all... because it was useless to panic. Who allowed him to travel through time to the most dangerous Fairy Tail world?! Let me ask, in a magical world, how can the final BOSS be defeated? What on earth? It would be better to leave this mess to the protagonist... All his life, Ian just wanted to hang out in the Fairy Tail guild and wait to die. Until the year X778, when a small crimson rice dumpling came to his door. Since then, Ian activated the dream simulation function. Ever since, Ian has crossed countless timelines to avert tragedy. In Ian's dream, he traveled four hundred years into the past and killed the general who killed Irene. He saved the Gray family and Ultear as well.