Test Mode:

Press and hold Up, A & B on the 2nd controller and press Reset. If done right, the test mode should appear.

 

Unlock The Endings:

There are 6 possible endings in this game. Finish the last stage with the following Pious Points and you'll get one of six endings. In addition, press A during the credits to see the princess dancing again. Bear in mind that you can only increase your Piousness in temples before the last level and killing enemies or picking money in the last level reduces your Pious Score.
 

Unlockable:                                                              How to unlock:

1- Namco Hall of Fame Ending                                 Have 19800 Pious Points And Don't Use A Continue

2- Heaven Ending                                                     Have 19800 Pious Points And Continue At Least Once

3- Human Ending                                                      Have 13000 - 19700 Pious Points

4- Cockroach Ending                                                Have 08000 - 12900 Pious Points

5- Ghoul Ending                                                        Have 03000 - 7900 Pious Points

6- Hell Ending                                                           Have 02900 Pious Points Or Lower