The Academy’s Weapon Replicator - Chapter 31.1: Menosorpo (6) Part 1

As a promise, he went out into the world as an assassin. 3 years later, after becoming the Supreme Assassin, he gave up on everything he had and returned to the ranks of ordinary people. But one day, Kismet, a mystical game created by the National Research and Development had appeared.

Enigmatic hands, spectral frame, and one cunning strike just like the swing of the Grim Reaper. The Supreme Assassin takes on the mystical world, and how his legendary tales sets off, progressively ascending the altar to becoming the best.

- Description from Novelupdates

Cao Xin, a young man on earth, died in a car accident, traveled to a troubled world where supplies were scarce, and obtained a “Bronze Immortal Gate”…

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- Description from novelbuddy

Ajax was an orphan who survives a massacre along with his friends but unfortunately gets separated from them.

Fortunately, after a turn of events, he successfully gains a system which helps him increase his cultivation, but doesn't know what it is called.

But he knows one thing for sure, this system is very powerful and helpful in taking his revenge.

“Whoever you are, I am gonna find you”, Ajax mumbled himself with a disgruntled expression.

In a world where Summoning of an elemental spirit is done through a dream when they are 15 years old, Ajax with the help of a system and his summoned spirits sets out on a journey to seek revenge against the mastermind behind the massacre.

Twelve years ago, an old beggar found an abandoned baby and took him as his own son, naming him Xu Han. But when his foster father dies, Xu Han finds himself in a training camp with dozens of other kids, though what they’re training for remains a mystery. It’s here that he meets his best friend, Liu Sheng, and life is good for a while — regular hot meals and a safe place to stay. But kids keep being taken and not coming back, and eventually, Xu Han and Liu Sheng find themselves left in the woods at night, where they discover what’s happened to the kids who disappeared before them — they’ve been turned into zombies! Can the pair destroy the zombies and survive the night, or will they be the newest victims of this twisted conspiracy?