Fully titled Ninja Gaiden Dragon Sword, the Team Ninja-developed title is a 3D action game that makes full use of the DS's most standout feature: the stylus. The entire game can be controlled almost entirely with the touch-based motions. You guide Ryu Hayabusa about the play field by tapping in the direction you'd like to go. Slashing the touch pen from down to up makes Hayabusa launch an enemy into the air, into a perfect position for combos. You make Hayabusa jump by tapping the screen twice, and can then point to enemies to shoot shurikens at them and perform a downward thrust attack. Even your ninja arts make use of the stylus, requiring that you draw shapes in order to perform the special attacks. Buttons are used only for defensive moves.
If an all touch-based Ninja Gaiden wasn't a big enough surprise, Ninja Gaiden DS has one additional peculiarity. The game is meant to be played by holding the DS with both screens lined up horizontally. This has presumably been done to give a tall view of the action on the touch screen, as the left screen is used to display maps.