Castlevania: Harmony of Dissonance Unlockables

After finishing the game you will unlock the Boss Rush option. There are three levels (easy, normal, and hard) that must be unlocked by playing each in succession, starting with easy.

Finish the game with the good ending (where you rescue Maxim and Lydie).

By collecting the Monster Tome relic while playing the game you will unlock the "Encyclopedia" option at the "Secret Info" menu, which details all monsters that you have defeated.

By collecting any collectible while playing the game you will unlock the "Collectibles" option at the "Secret Info" menu, which lists all the collectible items that you have found.

Once you can play as Maxim, you can do spells that Juste cannot. For example, face the right side of the screen and press Left, Down, Right, Down, Left + B to duplicate Maxim. The two copies will fly around the screen, attacking enemies.

Go to Castle B's Skeleton Cave. First, have the Griffin's Wing and go into the double exit save room near the entrance area with the big pillar. While in the save room, save the game then use the Griffin's Wing and go through the roof. You will get Wizard's Urn and Summoning Tome.

Finish the game to unlock the Boss Rush option. There are three levels (easy, normal, and hard) that must be unlocked by playing each in succession, starting with easy.

Unlock Boss Rush mode, then press Up(2), Down(2), Left, Right, Left, Right, B, A, Select at the Konami logo. Select Boss Rush mode to unlock the NES version of Simon.

Finish the game with the good ending (where you rescue Maxim and Lydie).