Reborn at Boot Camp: General, Don’t Mess Around! - Chapter 3603 - : A Brave Act

When Ye Mo suddenly woke up, he realized that everything around him seemed to have changed: He has been transmigrated into the modern Earth where spiritual energy is scarce. His pretty master from his former world was nowhere to be seen. Most importantly, he found himself in the body of a young man who has been abandoned by his clan for an embarrassing reason…

Kang Min-hyuk, the loser of the checkpoint, gained a high-level magical civilization and everything changed.

Seven years ago, Shen Qianshu is impregnated with Ye Ling’s child in an accident.
Seven years later, the little boy becomes famous and is thought of as the nation’s son.

When he suddenly sees Ye Ling appear, he greets, “Hello, Daddy?”
Ye Ling watches as the little prince roars, “Where’s my princess?”
Just as Shen Qianshu is preparing to run with her son, she gets pushed down by Ye Ling.

“You can leave if you want, but leave me a princess first. Let’s have another baby!”

- Description from Novelupdates

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.