Castlevania Double Pack

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

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

To play the game using no spellbooks, enter ''NOMAGIC'' as your name when you start a new game.

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.

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.

After getting the good ending(beat chaos) enter the name Julius in a new game as your name and youll play as julius

Beat the Game

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