In This Life, The Greatest Star In The Universe - Chapter 12:

Ye Xiao was a superior cultivator in his previous life. The three factions of the realm kill millions of people every time they attempt to seize cultivation resources. Wealthy towns turn to wastelands in just a single night. They cover up their crime with an assertion that the towns were suffering from pestilence and disasters.

They forcibly hold all the resources for cultivation, monopolize all valuable practice materials, and keep outsiders from cultivating so that only their three factions could cultivate in the realm. Ye Xiao declared war against the three factions in retaliation for their actions. He fought alone and ended up dying in vain. However, he is reborn into the mortal body of a 16-year-old boy. He will use the powers he cultivated in his last life and slaughter his way back into the Realm. The story begins!

- Description from Novelupdates

More than ten years later, this sentence gradually spread in Elbaf Continent:

Never use magic to deal with tyrants, because you will find that he will return your spells to you thousands of times after being strengthened by countless magic specialties.

This is the story of a dragon-shaped self-propelled fort that keeps doing things in another world.

There is nothing that one magic can’t fix. If there is, then there are more. ——Izawa

- Description from novelbuddy

In the third year of the Kaihuang era, as the Great Sui began to unfold between the fall of the Northern Dynasties and the rise of the glorious Tang Dynasty, Emperor Yang Jian created the House of Blades – an intelligence agency for strategies and conspiracies – in preparation to unify the world.

On a snowy night, a convoy of tribute from the Kingdom of Khotan was raided. Not one soul survived the attack. Feng Xiao, Second Commandant of the House of Blades, was ordered by the Emperor to investigate the matter in person.

On the distant border, a storm brewed as major forces gathered from all sides in Liugong Town. The strong rubbed shoulders with the strong; the skilled crossed paths with the skilled.

Here, the ever-successful Second Commandant Feng ran into a wall for the first time – all because of a feeble Taoist priest with ailing health.

Some things would never be known if no fights were ever picked. Only through their skirmishes did Feng Xiao realise that this sick bastard seemed to have way more aliases and personas than he himself ever did.

- Description from Novelupdates

[The false necromancer has insufficient soldiers and is being ostracized and hunted. ]

[The real necromancer, countless skeletons, become the overlord of one party. ]

After Wu Heng obtained the double portal, he discovered that the original world was full of zombies.

When a gangster’s plan fails, another plan to survive begins.

Wu Heng chose to become a ‘Necromancer’.

Is it not allowed to summon the undead from another world? In the last days, the entire planet is a source of soldiers.

Can’t survive in the zombie world? Then I will live in another world and learn skills.

From then on, an undead army equipped with modern weapons appeared in the world.

Natural disaster strikes, millions of skeletons.

Immortal Bone Dragon, King of the Undead.

(Double portal + necromancer + magic + fantasy world + undead natural disaster.)

- Description from novelbuddy