Ninja Assault
Mission mode Chapter 2:
Successfully complete Guren's Chapter in story mode.
Mission mode Chapter 3:
Successfully complete Gunjo's Chapter in story mode.
Mission mode Chapter 4:
Successfully complete Aoi's Chapter in story mode.
Mission mode Chapter 5:
Successfully complete story mode.
Mission mode Final Chapter:
Successfully complete all chapters in mission mode.
Fireworks training mode:
Get the top score in story mode to unlock the Fireworks
mini-game in training mode.
Magnum:
Successfully complete the Final Chapter in mission mode
to unlock a Magnum in story mode.
Shotgun:
Get an "S" rank in all the bonus training missions to
unlock a shotgun in story mode:
More credits:
You can gain one additional credit, up to a maximum of
twelve, if you lose all your credits in a chapter.
If you get to the very last Boss of the game on any chapter
except arcade, but get "Game Over" while fighting it, you
should get a screen that tells you that the number of
credits you have has now increased by ten.