Spy: My System Can Travel Through History

Brother? Hehe! In order to take away the secrets from me, they brutally killed me! Didn't expect it! I, Ling Han, am not completely dead! Bite! The ghost plan is activated, and the host will gain power beyond the times! Tokyo, Shanghai, Stalingrad... The system threw me into purgatory battlefields one after another! Very good! In the blood and fire of history, I sharpen the blade of my revenge! Kill through history, accumulate strength, then return to reality and send those bastards to hell one by one! My revenge never lasts overnight! My bullets are only loaded for the enemy!