Beat the game on Hard Mode. During the credits reel, there will be a different portrait of Vincent.
Complete the game with the best ending to unlock the following:
There are 3 Boss Rush courses where you face a string of bosses without breaks in between. Each course has its rewards if you beat it within a certain amount of time.
Depending on which Level Cap is used, defeating Hard Mode will yield different bonuses: non-sellable and non-usable "trophies" and permanent stat boosts. Defeating Hard Mode with a lower cap will automatically net items from the higher level caps. For example, defeating Hard Mode with Level 1 cap will give you all 3 sets of bonuses.
To perform this glitch, you need to have at least 1 item in your use inventory, otherwise you can't access your use inventory menu.Performing this glitch is different, depending on how many items you have in your use inventory menu.1 item in Use inventory: Touch the screen around the middle of the right side of the black space.2 or more items in Use inventory: Touch the small space between the top-right item and the edge of the screen.Doing so, will make the item description say "Restores 80 HP"Press "A" at this point to "Use" a potion.NOTE: If you have any normal potions they will be consumed, but if not, you will use a potion that doesn't exist. High and Super Potions will not be consumed.