Some wish fulfillment, a harem, nation-building, and resistance against Japan.
I transmigrate to the Naruto world and begin by occupying the Land of Waves. The System gives me daily rewards, and I gradually unify the entire shinobi world before invading other worlds and establishing a multiverse-spanning Huaxia Empire, so the Myriad Worlds will learn the might of our magnificent Huaxia.
(Warning: There are no Huaxia people in the shinobi world. Huaxia civilians will be brought over in other ways. As for the little Japanese devils in the shinobi world, many of them will become little Siberian potatoes. This is a heavily Naruto-focused story, and some readers may find its extreme nationalist and pro-China themes uncomfortable. Please read with caution.)
