Hold Up-Right + A + B when you are recuiting soldiers or equipping items. Garett MUST be highlighted when the buttons are pressed. All items will be available (including the Dragon Slayer) except for Warsong.

Note: This trick only works in the Japanese version. Also note that your cash will be reduced to zero if you do this.

This trick is a bit complicated, but it does work:

Begin a game.

Press A to reduce the map.

Move the cursor to the upper left-hand side corner of the screen.

Move the cursor one space right and one space down.
Hold B until a scenario number appears.

Press Up and Down to pick a stage.

You will begin the stage using the commanders you had when you entered the code.

To access the sound test, follow the Level Select instructions but enter the code on the normal map (don't reduce it.)

Item: Result:

Great Sword: +2 attack
Shield: +4 defense
Wand: +2 attack
Cross: +2 defense
Amulet: +2 defense, increased influence area
Warsong Big: + for attack and defense
Dragon Slayer Bigger: + for attack
Evil Axe Enormous: + for attack, big - for defense
Orb Magic: takes half as much energy.

I'm not sure how secret this is, but it's not mentioned in the manual. When a female Magic Knight reaches level 10, it can turn into a Ranger. The only problem is that a Ranger can't have soldiers of any sort. However, this isn't really a problem as she's EXTREMELY powerful.