The Time-Traveling King

In ancient village, Leo Shaw struggles with herbs, pushed to brink. Blood awakens jade pendant, opening two-world passage. Herbs become divine medicines in modern world, bringing fortune. Back in ancient world, uses modern tech. Flora is Empress of Great Zhou; her Green Capsule Classic is coveted. Leo rewrites book, dominates modern business. Facing Prince Letho's rebellion, Leo brings modern submachine guns, wiping out soldiers. Leo helps Flora ascend, becomes Eternal King, king of two worlds.