Unlock Meryl Costume
Complete the game on any difficulty setting twice after not submitting to the torture to unlock the Meryl costume.
100% success rate. 

Unlock Extreme Difficulty Setting
Complete the game on any difficulty to unlock the extreme difficulty setting.

Unlock Meryl Demo Mode
Complete the game on any difficulty setting after not submitting to the torture to unlock Meryl demo mode.

Unlock Otacon Demo Mode
Complete the game on any difficulty setting after submitting to the torture to unlock Otacon demo mode.

Unlock Otacon Costume
Complete the game on any difficulty setting twice after submitting to the torture to unlock the Otacon costume.

Alternate Ending Music
Complete the game on any difficulty setting three times for alternate music during the ending sequence.

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