Successfully complete the game to unlock the "New Game +" option. While entering a battle in the New Game +, hold L1 to hear music from the original Valkyrie Profile. While entering a battle in the New Game +, hold L2 to hear random music.
Easy experience
After defeating the Ballistic Rhino at the end of Royal Underground Path, you can fight it repeatedly. When prompted, go into the altar. You only get 1600+ experience points and 290 OTH, but you can also get a Baraka (an accessory that increases a character's HP).
Hard Mode
Finish the game to make any New Game playthroughs harder. The current difficult level is represented by crystals on the main screen. Every game clear adds one crystal, and 10 crystals will become a big one. The max is 5 big crystals (difficulty increased 50 times).
How To gain characters you wish without reseting the game
When ask to materialize refuse to do it for at lease 25 times to get the character that is hard to get.
Random BGM during battles
After you beat the game once,hold L2 while entering battle.
Seraphic Gate
Successfully complete the game and save when prompted after the credits. A new option will be unlocked on the world map that allows access to the Seraphic Gate dungeon through the cleared saved game file. Note: After completing Seraphic Gate, you can replay it with stronger enemies.
Unlock Dylan
Defeat Gabriel Celestia on floor 1 of the SG.
Unlock Freya
Defeat Freya on floor 4 of the SG.
Unlock Hrist
Defeat Woden on floor 2 of the SG.
Unlock Lenneth
Defeat Woden on floor 2 of the SG.
Unlock Leone
Defeat Gabriel Celestia on floor 1 of the SG.
Unlock Lezard
Defeat Obsessed Ex on floor 3 of the SG.
Unlock Silmeria
Defeat Woden on floor 2 of the SG.
Unlock Valkyrie
Defeat Ethereal Queen on floor five of the SG.
Valkyrie Profile 1 Battle Music
In New Game + just hold L1 while entering a battle.