Press [Up] [Up] [Down] [Down] [Left] [Right] [Left] [Right] [Aim] at the weapon equip screen.
Do not reload a gun if you are going to upgrade it. You will receive a full magazine when you do so.
Successfully complete the game to unlock a more difficult level of game play under arrange and original modes.
Hunk scenario and Extreme Battle mode
Successfully complete the game under the hard difficulty level with the best rank for Claire's A and B scenarios and Leon's A and B scenarios. Hunk is a soldier that must reach the second floor of the police station from the sewer with just battles and no puzzles. Extreme Battle mode unlocks Chris Redfield and Ada Wong as characters.
Successfully complete the entire game (both A and B games) three times in under three hours for each section and achieve a grade A or B each time. In addition, you must unlock the "Hunk" special character before you start to play through for the third time. Tofu's mission is the same as Hunk's except you are armed only with a knife.
Reach the police station without collecting any items. In the passage under the main door to the station will be a zobmied Brad Vickers (the helicopter pilot from the first game). Kill him and steal the "Special Key" from his body. This allows you to unlock the locker in the dark room under the stairs. Leon will have two new outfits, and Claire has one outfit and a new weapon. Note: If this is done in game 1, Brad will appear there again in game 2.
Special weapons and unlimited ammunition
Three special weapons with unlimited ammunition can be unlocked in the game. Using them will drop you one grade. To use them, complete the game and save it when prompted. The weapons will appear in the chests for that saved game.
Shotgun or crossbow
Complete a "B" game in under 3 hours with a grade of A or B.
Complete an "A" game in under 2.5 hours with a grade of A or B.
Complete a "B" game in under 2.5 hours with a grade of A or B without saving.
When playing as Leon go to the gun shop with the man. He will almost shoot you. After he dies because of the zombies, kill them. Then go up to the dead man and press "Action". You should get a shotgun. If playing as Claire you will get the crossbow.
Shoot the camera
It is possible to blow holes in the camera that follows your movements with the shotgun. Simply aim at the camera at a location where this is possible and fire. The cracks in the lens will quickly disappear.
There is film that can be developed in the dark room in the S.T.A.R.S. office, on the desk on the extreme left as you walk inside. To find it, simply search the desk approximately fifty times. Develop it to see a photo of Rebecca Chambers from the first Resident Evil game.