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:

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!


  1. Followed exactly --- 427 days, 18% cure completion, 5 biohazards, 150,660 score --- thanks!

  2. Gordon.. Nag much? Was a success mate!

    1. Towards the end.. Those that dident become infected, added bird 1,

  3. Hitting the Carribean is a big problem for me w/ this guide. Otherwise great.

  4. It worked. Some modifications added, like air (plane filters) and bird. Started in Russia 5/5 biohazard 395 days 20% cure 170 000 score

  5. 369 days 18% cure 5/5 biohazard 206000 score, at the end added bird 1 and 2 and also blood 1&2 as I had enough dna. This is a brilliant guide would recommend it to anyone ^__^

  6. Worked great! Followed the list exactly top down. Necrosis evolved on its own. Finished in 385 days with 18% cure (used two genetic reshuffles), 5/5 and 180,360 points. Thanks!!

  7. sweet!!! 225730 and 5 bios on the first try.

  8. Holy shit!
    338 days
    17% Cure Progress
    5 Biohazard
    237480 Total Score

  9. Joel Nathan JoedemanJune 28, 2014 at 3:14 AM

    Does anyone else get annoyed when you think you have it in the bag but you realize one of those stupid Islands like madaghascar, new zealand, carribean, or greenland, doesn't get infected, and their water ports are now closed? Thats just great isn't it? Plus, I think they should have a toss on times like these. In reality if the rest of the entire word was infected and dead, do you really think a little island of people is going to last forever? You can't kill every bird, livestock, insect, from making it to your island. And if you ever left, the dead bodies would still be infected, you would still be screwed. One island of 100k people is not going to stand up against the rest of the world.

  10. Great guide! Works on IOS 1.9.1. Thanks.

  11. Flavia Auditore da FirenzeAugust 13, 2014 at 11:36 AM

    Finished in 397 days with cure at 25%, 5 Biohazards.

  12. Flavia Auditore da FirenzeAugust 13, 2014 at 11:38 AM

    Dont evolve Bird 1 too early, do it only if they close down every other possible way of transmission.

  13. Out of 5 games, GREENLAND freaking won. How is that possible? I may either be really unlucky, or just really unlucky. I followed the instructions carefully but I really can't win.

  14. On all 5 games I might add

  15. Awesome! 5 Biohazards 1st try. 377 days 19% of cure.

  16. This worked really well. I just switched ATP Boost for Metabolic Jump and I had no problem with DNA points.

  17. Woah like what is you say the cure is below 30 thx

  18. Thank you so much! You guild so amazing. ^^