Dr. Mario
Metal Mario:

Play as Wario in Normal Mode in story and after you defeat Rudy you will get Metal Mario, but you can't lose, and redo is the same as losingVirus Multiply

In marathon mode, you can multiply the amount of viruses by pressing L or R.
Vampire Wario

Finish story mode on ant difficulty and defeat Vampire Wario to unlock him in vs mode but you can't lose, and redo is the same as losing.

Get Level 21:

Beat level 20 in classic mode to unlock the all new level 21 with 88 viruses.

Change AI Settings In VS. Mode:

At the Character Select Screen, highlight a character. Hold L and Press A to increase AI of that character. Hold L and Press B to decrease the AI of that character.
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