Reincarnator

Born from the idle whim of a bored god, the Abyss is an alternate reality that tears ordinary humans from their lives on Earth and hurls them into a merciless gladiator spectacle. Within its twisted arena, the abducted must battle not only nightmarish monsters but one another, killing or dying purely for their creator's amusement. Han-Su Kang has already endured this nightmare to its bitter end. One of only four humans to survive, he is granted an improbable second chance: cast twenty years into the past, he returns bearing the crushing weight of being humanity's final hope. Armed with memories of the catastrophe to come, Han-Su reunites with long-lost school friends—and former enemies—to reforge his skills and gather the knowledge he will need to face the horrors ahead. This time, mere survival is not the goal. Han-Su intends to shatter the god's cruel game once and for all.