Walkthrough for the impossible badge:
1. Restart the game until you get Cuba
2. Buy the following symptoms: Sneezing and Coughing. If you get Fever from the start keep it. Also buy Heat1, Cold1 and Moisture1.
3. When a region (not Cuba) have about 8000 infected sell Coughing and when it haves 30000 infected sell Sneezing and Fever.
4. Now wait till you have infected all countries (it may takes some tries)
5. When the last region is infected wait a couple of days.
6. Then buy Drug1, Drug2, Drug3 and Drug4.
7. Then buy Tier2 and Tier3 in the Symptoms section (keep the symptoms you get). Never buy Tier4.
8. Then buy the following symptoms in this order: Coughing, Hemorrhaging, Pulmonary Edema, Diarrhea, Kidney Failure, Hypersensitivity, Fever and Fatigue.
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 "Snail Bob 3"){kind=icon}