Ghosts Know What I Experienced - Chapter 36.3: Opening Coffins.

In previous life, I was just a mediocre guy, and accomplished nothing.

After reincarnation, I seize the opportunity of being a legend of the times. In this life, I am the protagonist in Tianxuan World, a great master of martial arts and a founder of making elixirs. What? You want to compete with me in weapon and equipment refining? Then, you should know the Craft God is my disciple…

- Description from Novelupdates

The king of assassins was reborn, mastering both alchemy and poison. Sitting inside the space, there was a ghost that loved crying.

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.

To rebuild death god’s glory, was our obligation!

At the start of the story, he and his zanpakuto had to fight for his own territory!

The Lord of Hell, Mephisto?

Playing with people’s hearts, you might need to learn more from me!

Necromancer?

Let me test the might of Ryūjin Jakka!

Iron Man, Tony Stark?

Come, come, it just happened that I am in need of technical support in the Technological Development Department!

…

Lod, who inherited the will of Soul King, crossed into Marvel World and decided to become the biggest behind-the-scenes manipulator!

When Lod ruled the three major organizations of the Wandenreich, Las Noches, and Seireitei, and looking at the entire universe, he could not help but sigh with emotion: In fact, at the beginning, I just wanted to live!