In the beginning of the game, you start with only the Throwing Star for a weapon. As you successfully complete bonus stages, a monk will offer you more weapons to use against your enemies.
Throwing Star
This is the standard weapon that Ninja-kun begins with. It travels forward in the direction that Ninja-kun is facing, a short distance (about half the screen) before disappearing. The speed of the star is influenced by Ninja-kun's momentum when he throws it.
Crescent Blade
The crescent blade is the first weapon upgrade that you will obtain if you complete one of the bonus stages in the allotted time. This weapon travels forward and slows down until it boomerangs back to the location from where it was thrown. Additionally, it rises and falls with your vertical position, although not as fast as you.
Bomb
The bomb is the second weapon upgrade that you can obtain through a bonus stage. Bombs are thrown in the direction that you face in an arc that rises and falls. They travel the shortest distance of any thrown weapon, but you can extend that distance a little by holding the shoot button down briefly before releasing it. Once they explode, the flash they leave behind remains on the screen briefly, damaging every enemy that comes in contact with it.
Fireballs
If you have bombs when you complete a bonus stage, you will be awarded with fireballs. Fireballs release four small flames that fan out in a counter-clockwise motion. These flames will pass through walls. Fireballs that you obtain through training can be used for 40 seconds, and you can switch to a different weapon at any time. However, if you obtain the fireball item (shown right) in the middle of a stage, it can only be used for 10 seconds, and you can't switch weapons until it runs out.
Sword
Ninja-kun does not have to earn this weapon, but it is only accessible when he is swimming. It has a very short range (about the size of Ninja-kun's body), but it is very fast and can be swung rapidly.
Normally, Ninja-kun can only throw up to two of each throwing weapon on to the screen at one time. However, if he successfully completes a bonus stage while still in possession of a fireball, he will be able to throw up to three of each weapon on the screen at one time.
Items
Rice Balls
Collect these rice balls to receive 3000 points.
Grapes
You earn 4000 points for collecting grapes.
Scrolls
When Ninja-kun kills one of the six basic enemies, it leaves a scroll behind. They are worth 100 points more than the number displayed when you collect them, plus an additional 100 points more if you clear the stage. The scrolls that you collect appear in the lower left hand corner of the screen. You can collect a maximum of 12 scrolls. (In the home conversions, this limitation is removed, and the number of scrolls is shown numerically at the top of the screen.)
Scrolls appear wherever an enemy is defeated. If you remain standing where an enemy was killed, the scroll will not appear until you move from that location. Scrolls remain on the screen for six seconds before they disappear if they are not collected. However, only one scroll can appear on the screen at one time. If you kill another scroll-producing enemy before the first scroll is collected, the first scroll will disappear immediately.
When you collect a scroll, there is a random chance that the face of a princess or a monk will appear. If a monk's face appears, all of your scrolls are lost. If a princess appears, the number of scrolls in your possession will double, up to a maximum of 12. Therefore, if you have 7 or more scrolls, you will only ever receive 12 scrolls. If you have 0 scrolls when a princess appears, you will still have no scrolls.
