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In this game, you wander around killing things - same as any number of other games. Your character starts with a certain amount of health, and every time they take a hit they lose one. Enemy monsters may have projectiles that they will try to throw at you, or they may simply try to rush at you. Most normal enemies die in 1-2 hits. The super-enemies you run into at the end of each stage (the 'boss' of that stage) will usually take a lot more.

Throughout the game you will also find various items inside treasure chests. These items heal, cure poison, make you invincible, and generally make your life easier. You can carry up to six at a time. Medicines of regeneration cannot be carried, but are automatically used as soon as they are found.

In addition to normal items, there are also magical power crystals. They do not count in your normal inventory, and you can carry up to six at a time. To use them, highlight the number of crystals you want to use, and press A. Your magic will be set to a level equal to the number of crystals used, and you will receive anywhere between one and twenty charges for that magic. As long as you keep magic (the icon with the M on it) as the equipped 'item', you will be able to use magic by pressing B. Each character has between three and five magic levels.

After you beat each act, you will receive the password for that act and the character you beat it with. You will now be able to go back to that stage by entering that password from the title screen.

You will be healed three health in between acts. You will also receive an extra health bar every ten thousand points.

[edit] General tips

• There is usually no reason why you should not constantly be attacking. Enemies take some time to react every time they come on screen, so if you're constantly pressing the 'C' button there's a good chance you'll cut anything in front of you down before they even fire. If you are Diane or Bead, you can destroy whole armies before they come within your line of sight. The only time when you shouldn't do this is when you know there are exploding enemies around. These monster types generally die very easily, and send out projectiles in several directions when they do.
• Stockpile lamps of life and dolls of life. They are lifesavers.
• If your inventory or power crystal stock is full and you come across something you'd like to pick up, use one of your items to free up a slot. Even if you don't plan on using magic any time soon, the spell charges will stay until you decide to use them. Magical crystals or items left behind in chests are gone for good.
• Keep your distance from enemies with ranged attacks. It gives you more warning, and therefore more time to dodge or block.
• You should learn the attack patterns of all enemies, but especially bosses, since you will be spending the most time dealing with their attacks, and bosses usually have the largest arsenal of weapons.
• Don't rely too much on magic or non-healing items like potion of invincibility. They are powerful but finite. Save them for tough boss fights.
• If you're stuck, try talking to people. Many hidden passages/items will only become accessible after your character finds out about them.