The Insider System - Chapter 3: Corn goes hard

Transcend to become the prince of Daxia, activate the Devil Emperor Summoning System, summon the powerhouses from other worlds, and fight for hegemony in the heavens!

If I were the Devil Emperor in the future, I would definitely let your blood stain the sky!

- Description from novelbuddy

[You have entered the dungeon at Gwachun Station’s 1st Exit.] When former high school student Kang Woojin finds himself returned back to Earth after being forcibly summoned to a foreign planet for 20 years, he soon finds that Earth is not the same, normal place as he once remembered it to be.

Living carefree at home is the greatest shortcut—- My house is the world’s greatest magic power spot, that being the case both my house and I were summoned to another world by some guys who were aiming for it. However, I’ve been living in this place for many years and my body is, apparently, abnormally overflowing with magic. Due to some unforeseen circumstances by those guys who summoned me, they quickly ran away. Be that as it may, there are some ill-mannered people who covet the magic leaking out of my house. I won’t give up my house to those people! I’m going to wield my power as I please!

The reborn Prince Hechingen of the Swabian branch of the Hohenzollern family, sees the situation in Europe, and the war is about to start, so Europe doesn’t wait. Enclosure in East Africa, immigration development, and agricultural foundation, step by step, with the help of the crisis to achieve industrialization.

- Description from novelbuddy