Castlevania Double Pack Codes, Passwords and Video Walkthrough (GBA)

The legendary titles Castlevania: Harmony of Dissonance and Castlevania: Aria of Sorrow are combined onto the same GBA cartridge, letting Castlevania fans experience twice the amount of evil and adventure in one convenient game package. Both chapters are among the most highly acclaimed games in the long running Castlevania franchise and will provide hours of portable gaming fun.

Castlevania Harmony of Dissonance is chronologically set 50 years after Castlevania II: Simon's Quest and 44 years before Demon Castle Dracula X: Rondo of Blood. Aria of Sorrow takes place in the year 2035 and stars Soma Cruz, a high school exchange student in Japan. (Wikipedia)

Codes

Play as 8-Bit Simon and Maxim in Boss Rush Mode (HoD)
After you've beaten the game and obtained Boss Rush Mode, input the Konami Code (up up down down left right left right B A) while the Konami logo is being shown. Enter Boss Rush mode and Simon will be automatically selected.

To play as Maxim in Boss Rush mode, press and hold the L and R buttons down when in the Boss Rush menu and hold them down until you enter the difficulty. You can now play as Maxim in Boss Rush.

up up down down left right left right B A - Play as 8-Bit Simon in Boss Rush Mode

Press and hold the L and R buttons down when in the Boss Rush menu and hold them down until you enter the difficulty Play as Maxim in Boss Rush Mode

Passwords

Hard Mode (HoD)
When selecting your name, make it "HARDGAME." This will enable you to play a harder version of the original game.

HARDGAME - Play Hard Mode

No Magic in Harmony of Dissonance
To play the game using no spellbooks, enter ''NOMAGIC'' as your name when you start a new game.

NOMAGIC - No Magic Mode

No soul use and no item use (AoS)
When starting a new game, type in NOSOUL as your name to use no souls in the game and type in NOUSE to use no items. This makes the game much harder.

NOUSE - No items

NOSOUL - No souls

Play as Julius in Aria of Sorrow
After getting the good ending (beat chaos) enter the name Julius in a new game as your name and you'll play as Julius.

Unlockables

AOS- Extended story
Before you fight Graham, equip the Flame Demon, Succubus and Giant Bat souls. After killing Graham, the story will continue.

Play as Maxim in HOD Single Player
Beat the Game

Maxim - type in maxim at the name screen

Unlock Boss Rush Mode in HoD and AoS
To obtain Boss Rush Mode in either game, simply beat them with a good ending or better.

AoS - Boss Rush Mode - Beat the game

HoD - Boss Rush Mode - Beat the game

Unlock Hard Mode (AoS)
Hard Mode - Beat the game with the good ending.

Unlock sound mode in aria of sorrow and harmony of dissonance.
To unlock sound mode in the games simply beat the game you want the sound mode for with the good ending.

Here's a short video walkthrough for Aria of Sorrow: