Shotgun Upgrades
When you enter Kirk’s Lab (The one with the escape hatch and vortex device), you will find a cabinet case next to the escape hatch. Push it out of the way, and you will find the stock upgrade for the PA3 shotgun.

And when you enter the stabilizer experiment room, there is a special code locked safe containing the second shotgun upgrade. Enter the code 1281 in to open it up, then the upgrade will change the shotgun from a PA3 to a SPAS12.

Operation Wipeout Mode
To unlock Operation Wipeout, beat the game in under 5 hours, or save less than three times, or don’t use any continues.

Secret Ending
Having trouble finding the 3rd ending? If you’ve played through to the end and chosen both Rick’s and Gail’s choices, then here’s the final ending you’re looking for. Have a feeling you’ve been through the game without visiting a few doors? You have. Three, to be exact. If you want to find it, you can simply access one of the Level A doors after you’ve chosen Rick or Gail’s decision. All of the unexplored level A doors lead to the same tunnel system. Simply follow it the secret heliport, then check your map and visit the red room. The red room will vary for each choice, so make sure.

Fourth Outfit
When you finish the game for first time, Regina will get two new costumes (Battle type, and Army type). If you play through the game twice, you will get a 4th outfit for Regina to wear. It will change her into a cave girl. Almost as though SHE came from the portal. An extra bonus for getting this is that if CHECK her guns at your EQUIP menu, they will have turned to an ancient type weapons. They will still function like normal, though.

Infinite Grenade Gun Ammo
When you have seen all three endings to Dino Crisis (you must play three separate games from start to finish). Regina not only starts with Grenade Gun in her arsenal, but she also has unlimited ammunition. Jackpot!

Bonus Outfits
If you beat the game in under 8 hours then you will get new costumes to wear as you play again