Three Kingdoms: Li Shimin Takes Li Jue's Place, and They Call Me the Heavenly Khan

Li Shimin, Emperor Taizong of the Tang Dynasty, transmigrates into Li Jue, the greatest villain of the late Eastern Han.

Cao Cao: Who's Li Shimin?

Liu Bei: Never heard of him!

Sun Quan: Who cares? Behold my army of a hundred thousand!

Li Shimin: Can the heroes of the Han compare to my Great Tang?

P.S. I've already completed a Three Kingdoms novel spanning several million words, so read with confidence.

P.S. The author's homepage has biographies of all the Three Kingdoms characters for reference.