Various cheats:

     To  unlock  cheats,  look  for  small,  glowing white orbs hidden
throughout  Transylvania.  Stand  on  one  and press Circle. A message
should  appear at the bottom of the screen with more information about
what was unlocked.

How to Unlock Cheats:

Unlimited Ammunition:
     Successfully complete the game under the hard difficulty setting.

Translucent Body:
     In  mission  two, get past the train station area and look behind
the "dragon" door.

Rifle:
     To get the Rifle, win all of the Easter Egg mini-games twice.

Archaic Clothes:
     When  battling Dracula for the first time in Castle Frankenstein,
a bunch of lab equipment will be near Velken off to the side. Look for
a  batch  of  green goo, jump in and click the action button until you
find  it.  You  may only keep it if you get it before killing Dracula,
otherwise you must go back for it.

Alternate Gatling Gun:
     When  starting  out  on  Mission  12,  you  will  notice  several
staircase platforms. Then wraiths will swarm at you from every corner.
Kill all the wraiths and make your way to the middle stair platform to
the  barred  door  to your left. Charge up the Alternate Lightning Gun
and  juice  the  power  stone in the wall. Walk inside and recover the
Alternate  Gatling  Gun. If you don't have the Rifle, this will do for
big damage.

Alternate Lightning Gun:
     When  escaping  Castle  Frankenstein  on  level  8, you will pass
through  familiar  rooms.  When  you  get  to the room where you first
encountered pygmy bats, jump through the hole in the wall in which you
came through to get there. As you jump down, you will notice a pool of
spilled  goo  off  to the side from one of the containers. If you look
closely, a glowing lightning gun will be lying in it.

Ghost Body:
     In mission two, look behind the "dragon" door at the start of the
train station to find the cheat icon. Use the alternate Tojo blades to
collect it.

Unlimited Speed:
     Just  after  entering  the side courtyard of Castle Frankenstein,
turn  left  (in  the direction of the tower). Double jump around until
you can see the cheat icon. Use the grappling hook to reach it.

Mission One Cheat Icon:
     When  you  first  use  the  grapple, you will see something white
glowing.  It is the cheat icon. After using your grapple, jump and get
it.

Big Head:
     In  mission  two, look near the Ghost Body cheat icon to find the
Big Head cheat icon near a wagon.

Armory Anytime:
     Find  the  large gear room in the Castle Frankenstein's basement.
Stand  on  the wooden platform on the right side of the room, then use
the  grappling  hook  to  reach  it. Alternately jump on the stallions
while  fighting  Demon  Verona  on the stagecoach. Get knocked off the
stallions  by  of  the  brides. An intermission that shows Van Helsing
getting  dragged  under  the  coach will appear. Repeatedly tap Circle
while  under  the  coach to collect the cheat icon. Alternately, first
complete  the  game  and get the Gatlin Gun upgrade. When you get into
the  gear  room, instead of going into the door, power it up and go to
the  other  side.  Use  your  grappling hook and it will take you to a
stone  door.  Use  your  Gatlin  Gun  upgrade  to start a intermission
sequence and it will be Armory Anytime.

Fell Skin:
     Complete  mission  five,  then  get  egg  in the well. Defeat the
werewolf  in  the town, and put the egg on a pedestal to get the cheat
icon.

Power Clothes:
     Successfully complete the game wearing your hat on every mission.

Small Fiend:
     In  mission  six,  enter  the  side entrance to the castle. After
defeating  the  werewolves,  walk to the lion gargoyle that is pouring
water and press Circle. The cheat icon is in its mouth.

Completion Bonus:
     Once  you  have  completed  the  game and wait for the credits to
roll,  you will be prompted to save your game on a new game option. Do
so  and  you  can  start the game with all previously unlocked cheats,
power-ups, and items.