Silpheed
Mania mode:
Press B(2), A, C, Up, Left, Right, Down, Up, A on controller two during the introduction sequence, then press Start on controller one. The score will be set to "00001" when game play begins to confirm correct code entry. This mode is more difficult than the "Hard Rank" setting. This mode can be canceled by entering the option screen. 

Super mania mode:
Press B(2), A, C, Up, Left, Right, Down, Up, A, B on controller two during the introduction sequence, then press Start on controller one. This mode can be canceled by entering the option screen. 

Level select/View FMV sequences:
Press Down(2), Up(2), Right, Left, Right, Left, A, B, Start during the introduction sequence. A "Stage Select" option will now be available. Select a level number greater than twelve to view the FMV sequences. 

Full shields:
Press Right, Left, A, Right, Up, C, B, Down, Left, B, A, Up, Start during the introduction sequence. Press A on controller two during game play to restore the shields. 

Unlimited continues:
Wait until only one continue remains during game play. Allow demonstration mode to begin when "Continue 01" appears on the title screen. Press Right, Up, A, B, C, Left(2), Down, C, A, Start during the demonstration sequence. Press Start when the title screen re-appears to continue game play with ten continues. This may be repeated as needed for unlimited continues. 

Debug mode:
Press Left, A, B, Up, Down, Up(2), Left, Right, C, Right, Down, B on controller two during the introduction sequence. A debug screen will be displayed. 

Voice test:
Select the "Options" selection at the title screen. Hold A + B + C on controller two and press Start on controller one. A "Voice Test" selection will now be available at the options screen. 

Pause demonstration mode:
Press Start on controller two.