Dr. Waldo Bloom

Dr. Waldo Bloom (sometimes shortend as Dr. Bloom) is a doctor who works at the Mushroom Kingdom Hospital. He only appeared in the Nintendo comic system comic The Doctor Is In... Over His Head he is in need of an assistant and Mario takes the job (as Dr. Mario). He seems to hate viruses and has a big microscope.

Dr. Bloom shows Mario and the Princess Peach through a hospital, showing off the room where they cure Mushroom People and enemies alike. He then brings them to his laboratory, where he explains that he's recently discovered Viruses that have been multiplying ever since. He has put the original specimens under a giant microscope, and the multiples in a jar. Just then, the original Viruses break loose from their container and land inside the giant microscope. Mario uses his plunger to open it up, releasing the now human-sized Viruses, who introduce themselves as Chill (blue), Fever (red), and Weird (yellow). After inflicting their respective sicknesses of coldness, heat, and weirdness on Mario, the Princess, and Dr. Bloom, the three break loose their smaller kin and escape through a window.

Mario takes off after the Viruses, but not before Dr. Bloom lends him his coat (which literally turns Mario's hair brown). Eventually, he finds a supply of Megavitamins that Dr. Bloom had stored in the coat's pockets and soon discovers that stacking Vitamins of a certain color on the same-colored Viruses eliminates them, so he proceeds to take out the Viruses. Afterwards, he returns to the hospital, only to find that Princess Toadstool, now in her nurse uniform, suggested Dr. Bloom to take up golf, and he's not returning to his duty until he's finished his game, though as Mario notes, that could take a very long time (Bloom has made 456 strokes and is still on the first hole).