Toaru Majutsu no Index: New Testament - Volume 16, Epilogue: A Model Answer that Exceeds Disaster - Nightmare_by_Lost_Boy.

He shall call forth the bone dragon! Summon the lich and the grim reaper! Li Jiayu, the dark summoner, has been reborn and everything returned to the moment before the outbreak of the devastating apocalypse.

Spaces tremble violently and dimensional cracks connected to various worlds appear! In an instant, never-seen-before civilizations invade our homeland. Insects the size of humans and walking corpses sweep through Earth in legions. An imminent crisis is approaching humanity and billions of human lives are at risk!

In regards to Li Jiayu’s uncorrupted soul, his summons shall no longer be limited to creatures which lurk in the darkness. They will also include the entities that bask in the light.

Under the lingering shadow of death, he vows to prevent a repeat of past tragedies!

Struggling within the exhausting apocalyptic world, he chooses to trudge on the bloody path of slaughter.

Walking hand in hand with death, he no longer lives under the cold embrace of the darkness. He shall embark on the bright path towards glory.

‘This is an opportunity to make a comeback… I will put everything on the line to right the wrongs and to protect the loved ones that were once lost.’

- Description from Novelupdates

Chu Nan was just an ordinary student, but because of an accident, he obtained the data collection, analysis and processing ability equivalent to the most advanced optical brain.

Transmigrating to a lawless person and then directly upgrading to a little brat’s stepmother. Xiao Ting said, “Crap, there’s no need to even give birth to a child. God, I love you so much …”

- Description from Novelupdates

Traveling to the wizarding world, Eli found that he was an Eternal.

Life is infinite, life is immortal.

“What? The talent is very poor, then I will meditate for ten years, centuries, and thousands of years, and I can always meet the promotion requirements.”

“This skill is hard? Oh, let me study it for decades to see if it’s really that hard?”

“Consuming life force, improving mental force, and this kind of good thing.”

“The enemy is here? Oh, let me find a place to hide for a thousand years, until his lifespan is exhausted and his mental power dissipates, and then I will come out again, free and endless void.”

…

This is the story of an immortal who lives in the wizarding world and then kills the endless world.

- Description from novelbuddy