Dr. Mario

From Zelda Wiki.org

Dr. Mario or Doctor Mario is an alternate Dx name for Mario, Dr. Mario is Mario in doctor clothing and although he does various things like curing biological viruses, he's well known for having a tetris-like game play, in the Nintendo game you cannot play Mario but you can arrange the pills in a certain way.

Outside of the Dr. Mario games, Mario is barely ever seen with anything dealing with medicine, it could be possible that Dr. Mario was a different person entirely because of this but this doesn't seem to be the case.

In Super Smash Bros. Melee, Dr. Mario is a hidden character. He has the same attacks as Mario and is a clone, but he has different ways of showing it; for example, instead of fireballs, he throws pills, and his cape attack is his lab coat. Successfully complete classic mode with Mario without losing a life to unlock Dr. Mario. Alternately, play 100 versus mode matches. Dr. Mario is not playable in Super Smash Bros. Brawl.