Boss challenge mode becomes available under the following two conditions. Both hidden Bosses (Ultimate Rugal, Shin Akuma) must already be defeated and unlocked. Hold B + Y and press Start while highlighting arcade mode.
Custom Grooves
The Custom Groove option appears once a normal Boss has been defeated (normal Akuma or Rugal). Normal Bosses appear by fulfilling two of the four following conditions.
Achieve over 1000 GPS by the end of the game.
Achieve four or more special KOs.
Middle Boss has appeared.
Achieve two or more LV3 super combo KOs.
Easy Boss challenge mode
Choose a good fighter such as Ken or Ryu. When you are facing the last Boss, if you are losing by one round and there is not a lot of power remaining, press Start on controller two and repeat until you win.
Use Haomaru the samurai. He looks weak and slow, but his slash and jump slash has a wide range and also does big damage. If you jump around with Airguard equipped and slash at the correct time, you will not have a problem defeating any Boss.
Easy survival mode
After unlocking the Extra Options, go to "Option Mode" at the main menu. Go to "Extra Options", select "Player One Life Gauge Type" and change it to "No Damage". Then, go to "Groove Gauge Type" and change it to "Infinite". After this, start survival mode and defeat all 46 characters without taking damage and your Groove Bar will always be full.
Extra color edit mode options
Press Start while editing the colors for your character to display more options on the left side of the screen.
Extra options
Clear Boss challenge mode with no continues. The "Extra Option" becomes available in the game.
Getting a Finest KO
Beat up your opponent until his/her life is low enough to finish them off with a special KO. Stand near your opponent and wait for them to taunt you. Then, do the special move and you will get a finest KO. You also have to either beat the mini-Boss, or receive 1500 GPS before you finish the final round in Osaka to get to Ultimate Rugal.
Hidden Bosses
Hidden Bosses can be used once they have been defeated. The conditions of the Bosses to appear are to fulfill two out of the following three conditions. If you play with a Capcom groove you will get Ultimate Rugal, and if you play with a SNK groove you will get Shin Akuma.
Achieve over 1500 GPS by the end of the game.
Defeat the Middle Boss (Geese or Bison/Vega).
Achieve at least one Finest KO.
Infinite custom groove
Defeat all characters straight in survival mode. The custom groove option settings will become infinite.
Middle Boss conditions
The middle Boss appears when the following conditions are all fulfilled:
No time over has occurred.
The CPU has not made over six "first attacks".
The CPU has not made three or more Special KOs.
One on three tag team mode
Highlighter any fighter at the character selection screen and press a button. Allow time to run out and the game will start in one on three tag team mode. Note: Do not select one on one battle mode.
Random Groove
Press Start at the Groove selection screen.
Street Fighter 2 music
Set up a match with Ryu versus Sagat in training mode. At times music from Street Fighter 2 will play.
Victory quotes
Hold Start + FP after winning a stage to make your character say an opponent specific quote. Hold Start + FK to make the character talk with a team member.