Hard mode:
Finish the game successfully on Normal difficulty,
set hard difficulty.
Level Selection:
Finish the game successfully to unlock all levels
at the same complexity that was originally set.
Unlimited Shield:
Complete each level successfully (including the tutorial level)
with difficult difficulty.
Unlimited Ammo:
Finish the game successfully on Normal difficulty
with rank “A” at every level (including training level).
Unlimited grenades:
Finish the game successfully on Hard difficulty with
lowest rank “B” at each level (including training level).
Unlimited Health:
Finish the game successfully on Hard difficulty with
the lowest rank “C” at each level (including the training level).
Selectable weapon:
Finish the game successfully on Hard difficulty, A-rank on
each level (including training level).
