- Joystick or : Use the joystick or direction pad to guide Ninja-kun. Press left or right to make him run in either direction. Press down to make him squat, or press diagonally down to make him crawl. Press up to change which weapon to throw if you have more than one. See below for more information.
- Jump or : Press the jump button to make Ninja-kun leap in the air. The longer you hold the button down, the higher he will jump. Press jump while running to make him jump in either direction.
- Shoot or : Press the shoot button to throw your currently selected weapon. You begin the game with only throwing stars, but you can obtain other weapons as you proceed.
- 1-2 Players or : Press to begin a one or two player game. Additionally, press the Start button on the Famicom to pause or unpause the game.
- : Press the Select button to choose between starting a one or two player game on the title screen.
You control the hero, Ninja-kun, who is capable of many dazzling ninja feats. Understanding how to control Ninja-kun is an essential aspect of mastering his adventure. What Ninja-kun is capable of depends upon where he is at the time. When Ninja-kun is standing on the ground, he can run to the left or to the right. When he is standing on solid ground that can't be passed through, he can squat down, or he can crawl in either direction. However, if he is standing on a platform, he can drop through it to the level below by pushing down. Note that if Ninja-kun has more than one weapon, he can select which weapon to use by pushing up. In fact, he can continue to run in either direction while selecting his weapon by alternating between right and up-right, or left and up-left.
Ninja-kun can also jump and throw weapons. When Ninja-kun jumps, the height of his jump is partly determined by how long you press the button for. Ninja-kun can also jump to the left or the right. Note that when Ninja-kun lands from a jump or a short fall, he must pause very briefly before he can continue moving. Similarly, Ninja-kun must pause briefly whenever he throws a weapon. He can only throw a weapon in the direction that he is facing (with the exception of the fireballs, which travel around him in a circle.) If he is walking when he throws a weapon, he will stop briefly while throwing.
Ninja-kun will lose a life if he is struck by a weapon thrown by an enemy. However, if Ninja-kun collides with a similarly sized opponent, he gets pushed away. If he runs into an opponent that is standing still, the opponent is pushed back. And if both Ninja-kun and an opponent run into each other, they will both bounce off of each other. However, there are some enemies that will kill Ninja-kun on contact, including bats, spiders, and anything underwater. Enemies that can be pushed away can be stunned if Ninja-kun jumps on top of them. If he does, they will be frozen in place momentarily, and vulnerable to your attack. Likewise, an enemy may bounce on top of Ninja-kun's head and stun him as well. Be careful not to become stunned when surrounded by enemies. If a larger enemy bounces on top of Ninja-kun, he will lose a life.
- There are a few possible outcomes if Ninja-kun begins to fall a long distance. While he is falling and not panicking, it's still possible to change the direction he faces and throw weapons. Once Ninja-kun falls too far, he begins to panic, and can't be controlled as easily. If he lands on the ground while panicking, he faints on the floor for a brief period, which you can end early by tapping the jump button. However, if you press jump just before hitting the ground, he will land on his feet, and you will earn a 1000 point bonus. When he begins to panic while falling, you can press the jump button, which will cause Ninja-kun to tuck into a somersault. At that point, you can press left or right while he is spinning, and he might roll when he hits the ground. If you don't press left or right, he may still land on his feet and you can earn the 1000 point bonus, but if he doesn't land on his feet, he will feint momentarily.
- Wall Jumping
- When jumping into a wall, Ninja-kun will rebound off of the surface. If you hold the joystick in the direction of the wall, Ninja-kun will grab on. Then you can tap the jump button to inch your way up the side of the wall until you find a ledge to climb up to. Climbing is very slow, but there is a faster way to climb up narrow channels by wall jumping. In order to wall jump, you must release the jump button, hold the joystick in the direction that points away from the wall, and press and hold the jump button in. Once he hits the wall, he will bounce off it with extra spring. To prepare for the next wall jump, you must release the jump button, hold the joystick in the opposite direction, and press and hold the jump button in again. As long as you release and press the jump button, and hold it down while holding the joystick away until you hit the wall, Ninja-kun will successfully bounce off of the wall. Being able to triangle jump at least once is essential to the completion of several stages. Being able to wall jump several times in a row will often help you complete bonus levels before time runs out.
- When Ninja-kun is in the water, a different set of controls take over. While swimming, you can press the joystick in eight directions to make Ninja-kun swim in that direction. If you tap the jump button while swimming, Ninja-kun will swim especially fast for a short distance. When you press the attack button, you will swing a sword. This sword can be used to attack and kill most small enemies that you encounter underwater, however it's not as useful against some enemies that are bigger than Ninja-kun. While swimming, it's also possible to hop out of the water and throw weapons while you're above the surface. Keep in mind that you will land back into the water with some speed, and it's not always easy to avoid enemies near the surface.