Unlock Bloody Palace Modes
     Beat  the  game with both Dante and Lucia to unlock Bloody Palace
Mode.  Bloody good! Complete the game on both Must Die Modes to unlock
Bloody Palace 2.

Unlock Bonus Costumes
     Beat  the game on any difficulty to unlock Dante's first costume,
and beat it on Dante Must Die Mode to unlock his second.
     Beat  the game on any difficulty to unlock Lucia's first costume,
and  beat  it on Hard Mode (with Lucia) to unlock her second. Beat the
game on Lucia Must Die Mode to unlock the third costume.

Unlock Dante Must Die Mode
     To unlock Dante Must Die Mode, beat the game on Hard with Dante.

Unlock Lucia Must Die Mode
     To unlock Lucia Must Die Mode, beat the game on Hard with Lucia.

Unlock Trish
     To unlock Trish, beat the game on Hard with Dante.