In Castlevania: Harmony of Despair for the Xbox 360, there is a hidden item in each chapter that will boost your end score when you collect them.
There are six hidden items to collect, so here are their locations:
Chapter 1 – Bell – You’ll find a room with three bells. Slide under the lowest one and jump up into it.
Chapter 2 – Crown – Use the yellow ledge to play the piano notes in this order, from left to right: 5th white, 5th black, 6th white, 5th white, 2nd black, 5th white, 6th black, 6th white
Chapter 3 – Moai – Fall through the center of the vortex in the background from the top of the stage.
Chapter 4 – Goemon – On the right side of the stage, go into the black alcove to make it appear.
Chapter 5 – Vic Viper – In the upper right hand corner of the stage, go down the hole to the right of the blue chest and fall to a platform. Go right as far as you can go and when you hit the wall, hold Up to make it appear.
Chapter 6 – Konami Man – Before the stairs to the final boss, jump up next to the blue roof and hold up for a few seconds.
