Boss Weapon Sting Boomerang Spark Ice Armadillo Spark Penguin Normal (yellow revving up) Sigma Normal (pink revving up) Sigma's dog Homing missile Octopus Storm
Password Description 0131-6712-1221 Sting Chameleon defeated 5447-4177-4536 Extra life tank 1556-6642-7448 Launch octopus defeated 8441-2136-4421 All bad guys dead, super x-buster, 9 powers, 9 sub-hearts, and 4 sub-tanks 3676-4627-5142 All sub tanks, all heart tanks, and all bosses defeated 7437-6412-1255 Start with everything
When you begin the game, don't go to the Sigma Stage. Instead, enter the Armored Armadillo stage.
Play to the end of the stage four times, keeping your Energy and Weapon meters at maximum. It's okay if you take a hit or use a weapon during the stage just be sure to recharge both meters by the time you get to the end of the stage.
Each time you reach the end of the stage, you must use the Escape Velocity to restart at the beginning of the stage. Remember, you must play though four times and always have full Weapon and Energy at the end of the stage.
After the fourth play-through, escape and restart one more time for a fifth try. This time, however, don't use the Escape Velocity. Instead, ride the third wheeled platform across the canyon and climb up the cliff before the entrance to Armored Armadillo's lair. On the top of the cliff, you will find a power-up capsule containing Dr. Light in a Ryu costume. He will give you the "Hadoken" Fireball technique!
You can throw Fireballs using the same motion used in SF II: Sweep the controller in a quarter-circle motion from Down to Forward and hit the Attack button. You can use the Fireball to kill all the final Sigma bosses with only one hit, but you must have full Weapon power to use the move. Remember, though, you cannot save the Fireball item using a password if you turn off the power, you will lose the weapon.