Sonic's Secrets: Castlevania Bloodlines.

Original Music.

On the options screen set BGM (Background Music) to 05 and SE (sound effects) to 073 (see right), make sure that these music settings are still set when you leave the options screen.
Now when your standard weapon is powered up to level 4, you will hear either Vampire Killer, Bloody Tears, or Beginnings, 3 songs from the NES Castlevania games until you get hit.

Expert Mode.

To activate expert mode, at the title screen (see right) press:

Up, Up, Down, Down, Left, Right, Left, Right, B, A.

You should hear a chime if the code was entered correctly.

A new difficulty setting (Expert) will now appear on the Options screen.  (see right)

Nine Lives!

Enter the Original Music and Expert Mode codes in order. I

f you did it right you'll now be able to choose up to 9 lives from the options screen (see right).