Use a controller in port two to play as Gary instead of James in single player mode.

Successfully complete original mode to unlock a selection for blood color on the options screen.

Successfully complete original mode to unlock the Goldman costume in the trunk of the car in the next original mode game.

Enable the "Infinite credits" bonus. Play through the game and shoot every hostage and try to get the lowest score possible. Towards the end of the game, when the last door is opened, Goldman will appear like a zombie.

Begin a game in original mode and select the 2.0 Bullets and the Double Score items from the trunk. Rescue all civilians except for the second person on level 4. Complete the game and enter the bonus room at the end. A Rogan Costume and an Infinite Credits item will be in the room.

Accumulate over 70,000 points and play on the "Sin" level in original mode. You can get the Bruno costume when a maid comes out of a secret room, hands it to you, and wishes you good luck. Note: It is a good idea to have the Double power-up when you are attempting to get the costume.

Successfully complete original mode without losing any civilians and with a score of at least 1000,000 points to reach a bonus room full of items at the end of the game.

Successfully defeat and obtain a high score ranking for all bosses in boss mode. "Emperor" and "Fight All Bosses" options will now be unlocked.

Successfully complete training mode with five red stars in each sections. This will unlock the infinite chamber item in the trunk in original mode that kills with one hit.

Successfully complete training mode and boss mode with five red stars in each section. Finally, get at least two stars in the fight all section. A continue infinity item will appear in the trunk in original mode.

Go to the fifth chapter in original mode to the section with the second battle the Boss that has the heart that opens and closes. Immediately following that segment, you will drive up to two vans with four zombies. Shoot the back door of the van on the left, then kill the zombies. Then the van on the right will open. Kill those zombies. When you turn back towards the van on the left again, shoot the coin with the infinity symbol to get unlimited continues. The coin will only appear if you have over 100,000 points. Using a double score bonus while playing is recommended.

You can also get the infinite continues coin in the Sin level in original mode. If you have over 100,000 points by the time you get to the Emperor, a secret room will open and a infinite credit item will be inside.

For more points added to your score when you complete a level, simply shoot various other items during a game. Shoot lamp post lights, lanterns, stacks of books, jars, tires on boats, windows on cars, chairs, and other furniture. Shooting barrels and drums, however, will not give you extra points, but may reveal items.

Successfully complete Boss mode with five red stars on all the Bosses. In the trunk of the car in original mode, you will have an item called 1/4 Life. This makes the zombies easier to kill.