Shadow the Hedgehog

Be a Metal shadow in 2 player mode. Don't be one with a bazuka. Hold down B in the air to use rapid fire shooting. You can also turn.

Complete the Hero storyline.

In most stages you have three choices: to help the Dark side, yourself, or the Hero side whenever you have someone with you and it is not a Boss fight. To change the character you want with you, press Start. There will most likely be three selections: Dark, Neutral, and Hero. Press Left or Right to highlight a character or ring in the middle. Press A to select the highlighted character. That character will remain with you until your next run in with the other character. You can then simply press Start and do the process again. Note: You cannot select a Hero partner if there is an "X" over the Hero side. You cannot select a Dark partner if there is an "X" over the Dark side. You can also use the D-Pad to change your partner. Press Right for the Hero character, Left for the Dark character, and Down for the Neutral character.

Go to the stage were you have to kill the Chaos. There is a room near two GUN soldiers and a Chaos that has two weapon boxes in it. Break both boxes, then go in the room with the GUN soldiers. Go back and the boxes will be there again. You can repeat this as many times as desired.

Complete the Neutral storyline with the Hero ending. Use the Egg Vacuum to suck up 20 objects to gain an extra life.

Get an "A" rank in all stages to unlock Expert mode.

The last level in the all Hero storyline is extremely tough to get through. To get to the goal, you have to go through the level without hitting ANY switches.

These are unlocked by getting all five keys in stages, and are located behind the 5-keyed doors.

There are 5 keys hidden in each stage of the game. If you collect them all, you will you'll unlock a secret door that leads to a special surprise.