Immortality Cultivation: I Farm in the System Space - Chapter 346 - 48 Black Xing Island

She, the “godly doctor” of an assassin organization in 21st century, transmigrated into the body of Yun Family’s abandoned, good-for-nothing Ninth Miss. Good-for-nothing? Then she’ll let the world see what a real good-for-nothing looks like. Summoners are legendary? Nothing is impossible in this world! She’ll become the first Magical Summoner.

QiLeren had just cleared the bad ending of «The Nightmare Games» when his laptop died well before its time. His luck seemed to follow him as he was transported, along with the other passengers, to a hospital following an accident between his bus and a truck. Upon waking in a transfusion hall rather than a ward, QiLeren felt a familiar sense of dread as he took in the hospital that held no trace of other people…

Book 1 of a Trilogy

- Description from Novelupdates

With a square halberd in the palm, and a red rabbit and horse under him, nowhere can the world go!

- Description from novelbuddy

The world was once at war with 10 alternate worlds. This was known as the Concept War and our world won 60 years ago. All of this was concealed so no normal people are aware of this fact in the current time.

After the death of his grandfather, the high-school student Sayama Mikoto is suddenly summoned by the giant corporation IAI. He learns this world is headed for destruction due to the acceleration of the Minus Concepts. To prevent this, negotiations must be undertaken with the survivors of the other parallel worlds so their 10 concepts can be released.

And so Sayama is caught up in the final battle to clean up after the Concept War which left behind so much enmity.