The story of Corpse Party: Book of Shadows is driven forward by fully-voiced dialogue and narrative, which players may advance with the X button.
If any lines have been missed, a message log is available for review on the ∆ button menu, containing a lengthy transcript of everything that's been said since the chapter began or the game was loaded.
If you've seen an event play out once before and wish to skip over it, simply hold the R button to fast-forward, releasing it once you've reached the desired point in the storyline.
If you come to a decision, think carefully and choose wisely, as the things you say and do can have an immediate (and often quite drastic) effect on the plot, leading to unpleasant "wrong ends."
Beware, though, as some decisions are timed, and failing to make up your mind before time is up could prove fatal!
When you see the Search Mode text appear on the upper-right corner of the screen, that means you now have full control over your lead character. Move the red targeting reticule around the room with either the analog stick or directional buttons, and if it turns blue, that means it's positioned over something (or someone) that can be examined or interacted with.
Press the X button to examine or interact with objects, people or spirits during Search Mode. This includes talking, opening cabinet doors, using keys in locks and other basic actions, as well as picking up items and reading memos.
During Search Mode, you can usually (but not always) press the L button to bring up a map of your immediate surroundings. While this map is displayed, you may position the red box around your destination and press the X button to begin walking there (or running, if you hold the R button). If you decide not to change your location, you may press the L button again to close the map.
Note that due to holes in the floor, locked doors, etc., certain locations may be at least temporarily inaccessible or impassable. These are represented by gray squares on the map, and attempting to select such a location (or any location on the opposite side of a gray square) will have no effect.
Beware, too, as obstacles will often pop up between you and your destination, interrupting your trek with an event scene that may unexpectedly drop you back into Search Mode in a dangerous and/or undesirable spot.
As in the first Corpse Party, the students under your control are neither the first nor only victims to be whisked away into the hell that is Heavenly Host. During the course of your struggle, you may encounter the remains of those who came before you, most of whom still have their student ID name tags intact (albeit buried within rib cages or lodged beneath unnameable viscera).
At any time during play, you may open the ∆ button menu to check your Name Tag List for a comprehensive overview of all the unfortunate souls you've thus far identified.
Your character will encounter corpses (both fully intact and otherwise), crazed writings, malevolent spirits, booby traps, hordes of insects and innumerable other horrors within Corpse Party: Book of Shadows' many cursed grounds. Each time something truly frightening is experienced, your Darkening meter (visible on the ∆ button menu) will be raised. As it climbs closer and closer to 100%, distortions begin to appear on the screen, growing in intensity and increasing in number as the Darkening takes hold of your mind.
Once your Darkening has passed certain thresholds, your characters may begin to lose their ability to reason, causing them to see and react to the environment differently than they otherwise would.
If any character's Darkening should reach 100%, the game will conclude with either a haunting "wrong end" or a straight-up Game Over...