Start a New Game with the Alternate Storyline
     The  Alternate  Storyline  is  normally  unlocked  by  collecting
various  letters  throughout  the game, but it can also be unlocked by
entering  the  following code at the title screen, with the pointer on
"New Game." There will be a voice confirmation if successful.

[Triangle], [Square], [X], [Triangle], [Square], [X], [Circle]: 
Unlocks Alternate Storyline (JP)



Extra Stage
     Cave of Ordeals Collected 70 Lucky.



Fight Etna
     To  fight  Etna  you  must  collect 100 Lucky then choose the 3rd
option in the castle door to fight her.



Alternate Endings
     Here is how to unlock the different endings.

A News of Explosion Penguin - Lose all 1000 lives

Asagi Ending - Beat her game in her story mode

Normal Ending - Beat the game normally

The Escape of the Prinny - Talk to the Ninja and pick the first option



Secret Move
     Prinny Raid Skill - Die 1000 times and start a new game+



Asagi Mode
     Collect all Torn Letters



Kill Yourself
     Hold [L]+[R], then press [X]. You Prinny will explode, and then 
you'll start from the last save point. Very useful when you want 
to restart a boss fight quickly.