Slow Motion
If you wish to slow down the speed with which Casper travels, you'll want to enter this code: hold Triangle and press X , L1, L1, L1 during game play. Once you're done going slow, press Triangle to resume normal game play and speed.
Faster Game Play
If you wish to achieve faster game play, hold the Triangle button and press X, R1, R1, R1 during game play. As you enter this sequence, the inventory screen will appear. You can disregard it. When you're finished with this mode, press the triangle button to resume normal game play.
Achieving Free Movement
To experience "free movement" and fly over walls, move Casper to the upper left corner of a location and hold Up/Left while pressing L1 + R1 + Start. This pauses the game. Then, release Up/Left + L1 and press Down/Right + Triangle while still holding R1+ Start. The game will start again in free movement mode. If you wish to fly over any wall, press the R1 button and then use the D-pad to move. Press L1 at any time to resume normal game play.
Morphs and More
While you can use the puzzle pieces to get the necessary morphs to finish the game, there is an easier and less frustrating way. Activate the "free movement" code mentioned earlier. Complete this step at the start of the main hall that has the floor that twists. From here proceed up the staircase on the left. Wait until the next section is done loading, and then press the R1 button to scale the wall. Continue down until a secret room appears. In this room, you'll find all the morphs, plus other bonuses.