Not all decks need Dr. Boom. Many decks do use him, of course, but many decks don't curve that high. Any N'Zoth deck is usually glad to have the doctor, of course, but Egg Druid, Pirates, and many Reno decks simply choose not to run Dr. Boom. There is no 'must-have' cards in wild in the sense that every deck runs them, but Dr. Boom, Loatheb, Mad Scientist, and Sludge Belcher see play in many different decks, and are good first choices of cards to craft if you're just getting into Wild.
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