If you are running low on Ghost Energy for any of your guns, shoot a rat to get more. Note: If you shoot a rat, leave the room, wait a minute, then go back in. The rat will be alive again.
Invincibility
Without pausing the game enter: hold RIGHT and L3 for 5 seconds or more then press TRIANGLE.
More Damage
While playing, press right and hold the L3 buttons. After 5 seconds, press the circle button. Now Lazarus should be able to inflict greater damage to the ghosts.
Pass Through Building
In the weird mansion after collecting the kaleidoscope, the girl tells you another riddle and you will go through another door into a room with a projector. Summon Astral and fly into the corner with the rocking horse. Position yourself above the horse, then use Astral's abilities to walk. If done correctly you should drop in to the corner and be pushed outside the building. Return to flying mode and fly around the outside of the room. You might see things that can help you solve the puzzle.
Slides of Montsaye murder in Montsaye High
The first time you visit Montsaye High (the very first level), after freeing the ghosts and the intermission sequence with Hawksmoor and Anna in the attic, but before you go there, go to one of the classrooms that appears to be a science-type room. On a table near the window is a television and slide projector. Approach the projector and an option for action appears. Press this button to see a mysterious shadowy figure. Press it again to see another image. Keep doing this until you return to the original slide.
View Ghosts
After you have captured the medieval ghosts and captured the blue spook and the revenant in the attic, there will be an intermission sequence. You will now be able to view the ghosts you have captured through a viewing panel where Lazarus released the ghosts, at any time throughout the game. Note: You can only view the ghosts when you are at Montsaye High.
Get Ghost Energy quickly...