Press 'Pause' during gameplay and enter the following codes to enable the corresponding effect.

The next block in line will become a Karakuri Ken scroll, destroying random blocks in your stack.
Press Left, A, Right, B.

The next block in line will become a Koume scroll, destroying 3 Horizontal lines under her:
Press Up, B, Down, B.

The next block in line will become a Zenmai scroll, destroying a Vertical line:
Press Up, A, Up, A.

Enter the following codes at the 'Mode Select' screen to enable the corresponding feature.

Play Vs. Death Level:
Press Down, Down, Up, Up, B, B, Up, Up.

Unlock Vs. Level Select:
Press Up, Up, Down, Down, B, B, Down, Down.

Enter the following codes at the indicated point of the game to enable it's effect.

ALL Shots will be 2 times as Powerful:
At the 'Title' screen press Up, Left, Down, Right, Up, Left, Down, Right.

Be in a Permanent 'Alert' Condition:
At the 'Title' screen press Up, up, Left, Right, Down, Down, Left, Right, Right.

Be in a Permanent 'Danger' Condition:
At the 'Title' screen press Up, Up, Left, Right, Down, Down, Left, Right, Up.

Be in a Permanent 'Good Luck' Condition:
At the 'Title' screen press Up, Up, Left, Right, Down, Down, Left, Right, Down.

Be in a Permanent 'Safe' condition:
At the 'Title' screen press Up, Up, Left, Right, Down, Down, Left, Right, Left.

Death Mode (No Gun Units available):
At the 'Title' screen press Down, Left, Up, right, Down, Left, Up, Right.

A Gun Unit Roulette appears on Screen:
Press pause during play and enter A, B, A, Right, Left, Down, Up (this code can only be used once).

Continue from where you were:
On the 'Game Over' screen hold Left and press 'Start'.

Power Up:
During gameplay press 'Pause' and enter Up, Up, A, A, B, B. This code can only be used once.

Enter the following codes where indicated to activate the corresponding effect.

Become Fully Powered Up:
Pause the game and press Down, Right, Up, Left, B, B, B, B, A, A, A, A. This code can only be used once.

Gives 3 Scrolls:
Pause the game and press Up, Right, Down, Left, A, A, A, A, B, B, B, B. This code can only be used once.

Lets you Continue:
On the 'Game Over' screen hold Left and press 'Start'.

Enter the following codes where indicated to activate the corresponding effect.

Start the game with 99 Lives:
At the 'Title' screen press Up, Down, Up, Down, Right, Left, Right, Left.

Invincible:
During gameplay press Down, Up, Down, Up, Left, Right, Left, Right. This code can only be used once.

At the 'Title' screen press Left, Right, Right, Left, B, B to play the 'Reversed Stage' where one part of the stage will be different.

If you clear the game without killing more than 13 enemies (this excludes asteroids and bosses in the Asteroid Zone) you will be able to view the alternate ending.

Hold Left when selecting a 'Class' and then press 'Start'.

When you have cleared the second Kancho wa Meitantei game (kouhen) press Right, Left, Right, Left, B, B at the 'Title' screen to be able to play freely the boat chase part of the Story mode. This feature won't work if you have not cleared the game.

When you have cleared the first Kancho wa Meitantei game (Zenpen) press Left, Right, Left, Right, B, B at the 'Title' screen to be able to play freely the bike chase part of the Story mode. This feature won't work if you have not cleared the game.

Enter the following codes at the indicated point of the game to unlock the corresponding effect.

Unlock Stage Select
Press Up, Up, A, A, B, B at the 'Title' screen.

Continue from Level you Died on:
Press Left + 'Start' together at the 'Game Over' screen.

Enter the following codes at the indicated screen to enable the corresponding effect in the game.

Continue from Level you Died on:
Press Left + 'Start' together at the 'Game Over' Screen.

Invincibility (can only use once):
Press Right, Left, Right, Left, Down, Up, Down, Up at the 'Pause' screen.

Start Game with 99 Lives:
Press Left, Right, Left, Right, Up, Down, Up, Down at the 'Title' screen.

At the indicated point enter the following codes to unlock the corresponding feature.

Unlock Death Level:
Press Down, Down, Up, Up, B, B, Up, Up on the 'Mode Select' screen.

Unlock Vs. Level Select:
Press Up, Up, Down, Down, B, B, Down, Down on the 'Mode Select' screen.

Enter the following codes at the indicated point of the game to enable their effect.

Start from Second Play Through:
At the 'Title' screen press Left, Right, Left, Right, Select.

Continue from Level you Died on
At the 'Game Over' screen press Left + 'Start' together.