Hard mode
Successfully complete the game under the normal difficulty
setting to unlock the hard difficulty setting.
Level select
Successfully complete the game to unlock all levels
under the same difficulty setting initially used.
Unlimited shield
Successfully complete each level (including the training
level) under the hard difficulty setting.
Unlimited ammunition
Successfully complete the game under the normal difficulty
setting with an "A" rank on each level (including the
training level).
Unlimited grenades
Successfully complete the game under the hard difficulty
setting with at least a "B" rank on each level (including
the training level).
Unlimited health
Successfully complete the game under the hard difficulty
setting with at least a "C" rank on each level (including
the training level).
Selectable left-weapon
Successfully complete the game under the hard difficulty
setting with an "A" rank on each level (including the
training level).