VIDEOS:
Minos Prime
In order to confront Minos Prime, you first have to enter a secret door in 3-1 that only opens after you P-Rank every single level in the Act. THEN you have to first defeat the Flesh Prison containing him, an extremely challenging boss in its own right. Only after that are you able to fight Minos properly, and he proves to have some of the highest speed and aggression out of any boss in the entire game.
Example of:
Superboss
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