The Fake Mad Prince's Gambit

A modern special forces soldier transmigrates into Jasper Lyon, Deposed Crown Prince, on death row. To survive, he feigns madness, evades assassination. Escaping, he allies with Rowena Grant. They train inmates into elite troops, rectify corruption, implement new policies. When foreign enemies threaten, he introduces technology, crushes them, building a powerful Great Zenith Empire from the "mad prince".