Clear the game with Leon once and save that game. Start a new game on another slot and enter the name @LLSKILL. Leon will have all his skills when he begins the game.
Duplicate items early in the game (NA Version)
You can duplicate items early and a very easy way early in the game. First off you must have at least one of the items you want to duplicate. Example would be a High Potion. Now go to the very first save point in the game. Its on Leons right as he enters the castle. Now before you actually go to the save point you really just need to go to the hall where the save point is. If you walk on the left side of the screen on the red part of the carpet you should see a green part of the floor where it looks like the moon is shining through green. You need to stand on the red part of the carpet facing the window on the green spot of the floor. Next press start and go to items. Scroll down to the item you want to duplicate. You should notice that all of your items are going up by one. You can get a max of 9 in normal mode and 5 in Crazy mode doing this. You can do this for any item. Try it with a gem like a diamond then sell the diamonds back to get infinte money.
Duplicator Glitch
There's a way to duplicate your items. Enter the castle and head to the door that leads to the Save Room and the room to the other 5 stages. In the hallway near the Save Room, look on the carpet for a green spot of color. Go stand on it, facing the window and open up your subscreen and go to your item list. By scrolling through your item list each item mysteriously increases by one.
Duplicator Glitch #2
There is a second spot inside the Pagoda of Misty Moon where items can be duplicated (again). On the second floor hallway, stand near the second circle design on the carpet (on the map, it will be near the east side of the stage). Press START to enter the item screen and glitch away.
Duplicator Glitch #3
The hallway outside the VI Stone room allows items to be duplicated through the start menu (see Duplicator Glitch #2).
Fire Whip
First, go to the Anti-Soul Mysteries Lab second floor and find the room with the moving platform. Follow it until you get to the second platform on the right. After jumping over the platform, look for two yellow poles. Hook over the two poles. On the upper side, you can find the monster named Flame Element. Defeat him and he will give you the Fire Whip.
Item Duplication - Pagoda Of The Misty Moon (US Version)
There's another way to duplicate your Items, instead of doing it in the Prelude To The Dark Abyss/Castle Entrance. On Floor 2 of the Pagoda Of The Misty Moon, just as you enter the Floor, nearby on the carpet is a circle design. Stand near it and enter the Menu and head to your Item List and duplicate away.
Unlock Boss Rush Mode
Clear the game with any character and save that game. That game's character may head back to the stage select room and opt to try Boss Rush Mode, that is a time attack mode against all the bosses in the game in the order they appear in the Encyclopedia.
Unlock Crazy Mode
Clear the game with Leon once and save that game. Start a new game on another slot and enter the name @CRAZY. Crazy mode is much harder than the normal game, and Leon starts with a defence of zero.
Unlock Jade Mask Item
Clearing the game will unlock the Jade Mask for sale at the shop.
Unlock Joachim's Game
Clear the game with Leon once and save that game. Start a new game on another slot and enter the name @JOACHIM. Joachim's game is played differently, and the character has no access to any weapons, armour, or health restoration items.
Unlock Mobius Brooch Item
Clearing the game on Crazy Mode will unlock the Mobius Brooch in the shop.
Unlock Pumpkin Game
Clear the game with Joachim once and save that game. Start a new game on another slot and enter the name @PUMPKIN. The Pumpkin game starts the character off with all skills and the Vampire Killer, as well as increased stats. However, there are no subweapons available other than the initial subweapon.
Unlock Sound Test
Clear the game once with any character and save that game. The Music Box will be available for purchase in Rinaldo's shop for all future games (you only need to buy it once and save the purchase to that game).