Access to Sound Test:
     Press B + Start at the Diary (save select) screen.

Best Players Screen
     Go to the title screen and press B + Start.

Instant weapon switch (without open the weapons menu up):
     Hold Mode and push B. Note: You need a 6-button controller.

Teleport to a hidden island:
NOTE: You have to get the Warp device first!
     Go to the seashore on the lower west side of the map. Use Shade's
Doppelganger to locate the invisible silver crack (the warp), then use
your  Warp  Device to open up the warp. You'll then be teleported to a
hidden island.


Secret Moves:

Stab
     Press Forward, Forward, Forward, B Flash

Flip Splash
     Hold B, press Forward, Backward, Forward, and then release B

Grand Spin
     Hold B, rotate the D-Pad clockwise, and release B

Sword Flurry
     With  any sword equipped, 360 motion on the d-pad, forward, back,
forward, B, pause for half second, B

Triple Flip
     360  motion  on  the  d-pad, forward, back, forward, B, B, B (can
also be ended after the 1st or 2nd flip)