Plague Inc. Prion Mega-Brutal Guide/ Walkthrough/ Strategy

Surprisingly, I found an amazing strategy for Prion within a few games. I always finish within 400 days, have a cure completion of less than 30%, and a score of 5/5 Biohazards. Okay, not always but most of the time. The only hard part about beating prion, in my opinion, are the random Genetic Shifts. If you have no idea what these are, they're random events that happen which increases or decreases the DNA costs of everything. Genetic Shifts tend to increase most of the time though.

Prion takes awhile to take the effect of whatever evolution you just made, but it makes up for that small setback by being hard to detect and to cure. It's unique abilities help improve high scores because it slows down the cure progression. Combine these abilities with Genetic hardening and symptoms that does the same, the cure slows down to a crawl.

The only thing I think you need to worry about are Genetic Shifts since they almost always increase the DNA costs of everything. We'll be counting on some mutations of symptoms to save some DNA but the random shifts will still be a pain in the ass. Expect unreasonable DNA increases, I once had one game where a 27 DNA evolution of Necrosis turned into 57.

First off, Gene setup:

• ATP Boost
• Aquacyte
• Sympto-Stasis
• Genetic Mimic
• Extremophile

1. Start in China

2. Evolve the following symptoms: (order does not matter)

• Rash
• Nausea
• Coughing
• Cysts
• Anaemia
• Haemophilia
• Hyper Sensitivity
• Abscesses
• Pneumonia
• Sneezing
• Sweating
• Vomiting
• Diarrhoea
• Skin Lesions

3. Evolve Water and Insect 1 then Water and Insect 2

4. Evolve Drug Resistance 1 and 2, then Cold and Heat Resistance 1 and 2

5. Evolve the following symptoms:(order doesn't matter, but is recommended)

• Insomnia
• Paranoia
• Seizures
• Insanity
• Paralysis
• Coma

6. Evolve Neural Atrophy 1, 2, and 3, Then Genetic Hardening 1 and 2

7. Evolve Total Organ Failure if it has not mutated yet. 

(This is optional but you could choose to evolve Necrosis if Total Organ Failure has already mutated.)

8. Remaining DNA is best put to evolve Genetic Re-Shuffles to lower cure progress which increase high score

Now just wait until your Prion plague eradicates humanity. I hope this guide has helped you beat Prion in mega-brutal difficulty. In my experience, better high scores are obtained if you're lucky enough to mutate certain symptoms. In this strategy's case, mutating Necrosis, Dysentery, and Total Organ Failure would save you a lot of DNA and would infect and kill people faster.

Alternate Strategies:

• Unknown Origins Scenario: Prion Guide

That's it. If you guys have any tips, question, or another strategy post them at the comments below. I'll include the good ones I test out along with this guide. Happy gaming!