Transmigrating to the Three Kingdoms to Become a Warlord

An accident made him transmigrate to the Three Kingdoms era. He had hoped to unite the realm, standardize the roads and written language, and become a wise emperor like the First Emperor. But another accident let him witness his countrymen being slaughtered by foreign tribes. So he decided to become a warlord who invaded only foreign lands. And so the Three Kingdoms lost an emperor vying to rule the realm, but gained a sleazy warlord who invaded everywhere...