Luxor 2 HD Cheat mode
Enter the “Options” menu, then [Page Up] + [Page Down].
Bonus lives remaining and real ending
Successfully complete the game, then do not click the next difficulty.
Challenge Of Horus
Successfully complete the game on the Hard difficulty to unlock the Challenge Of Horus.
The image featured at the top of this post is ©The Legend of Heroes: Trails of Cold Steel III key art.