The Great Battle between Karus and El Morad has arrived to Steam! Pledge allegiance to one of the Nations and put your skills to the test in one of the best PvP. Knight Online is a leading party based medieval MMORPG that is, and will alyways be, Free to Play! Register now and enjoy Knight Online. Client Download. You need to install the game client for game play. The game may not run properly if your PC is below the minimum PC requirement. Knight.