3 secret bosses are hidden in the Special score attack mode. They are appear according to your final score, prior to reaching the boss.
~30,000
Kaitou Midori Mantou (The Mysterious Green Cloak)
900,000~1,000,000
Shokutsuu Daiou Manjiri-kun (The Great Gourmet King Manjiri-kun)
1,000,000+
Super DX Koutei Penguin (Super Deluxe Emperor Penguin)
Scores outside these ranges mean you will see an in game boss instead.