Dino Crisis cheat codes:
Alternate costumes:
Successfully complete the game to unlock the
Army and Battle costumes for Regina. Successfully
complete the game a second time to unlock the
Ancient (caveman) costume.

Grenade gun:
Successfully complete the game three times.
The grenade gun with unlimited ammunition will
be available at the start of the next game.

Operation: Wipe Out mode:
Successfully complete the game with a time under 5:00:00.

Puzzle preview:
When at a puzzle, before changing it, around push
the button. Nothing will happen, but if you watch
the colored lights they will turn on in the order
needed to solve the puzzle.

Shutters:
Since the dinos can not pass through a shutter, use
them to your advantage. Close each shutter after you
pass them. This way, if a dino appears in that particular
area, you can not be attacked (unless, of course, you
are on the same side as the dino).

Save ammo:
There are some areas that you will only pass
through once or twice in the entire game.
Killing the dinos in these areas is pointless;
more importantly, it is a waste of ammo.
Use the weakest tranquilizer dart on it/them,
and move on. This way, the bullets/shells/slugs/grenades
are available when you need them. Once you get unlimited
grenades (by completing the game three times under the
normal difficulty setting),
you can kill those dinos, without wasting ammo.