Start a match and have both players remain idle for about 10 seconds. Eventually a remixed version of a character's classic themes will start playing. Note: The theme is stage specific and any action will cause the music to fade back to normal.
After unlocking the three Endings of a character, play through Arcade mode in Medium or higher difficulty and without losing a single fight. After defeating Fulgore, you will face Shadow Jago. Note: Shadow Jago is always set to Kyle Difficulty and unlocks whether you win or lose the fight.