Global Catastrophe: The Underground Fortress

This story takes place in one of countless parallel worlds. Everything is fictional, so don't associate it with reality!

[System, Invincible, Technology, No Heroine, Ruthless and Decisive, Selfish, Showing Off, Dark Tone] The protagonist focuses on building up his strength early on and becomes invincible in the middle and later stages. The first six tags are the main focus, while the last two are secondary. Do-gooders, please move along!

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Ye Feng accidentally transmigrates to a parallel world in the apocalypse. Using the System, he improves his fortress to withstand waves of monsters and demons, recruits guards, unlocks technology, explores the wasteland, and slays foreign races, all while enjoying a happy life with plenty to eat and drink.

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The monsters and demons attack me, but I don't feel a thing. They just fall over. Since Ye Feng can't attack of his own accord, he can only be forced to play dead, wandering aimlessly around the battlefield with a shield in hand. Boredom eventually makes him cause all kinds of trouble on the battlefield, complete with his own invincibility effects!

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Survivors: Please, have pity on us and take us in!

Ye Feng: “Someone, take them all away and mow them down! What a pain!”