Plague Inc. Unknown Origin: Bacteria Mega-Brutal(3 Biohazard) Guide

Click here for a list of plague guides for the Unknown Origin scenario.
This guide also works for normal games, since you're able to select your starting country.

The Unknown Origin scenario is just like any other normal game, but instead of being able to start in a country that you want, it's going to be decided for you. There are different strategies for every country, different order of evolutions you must make, and different rates of infection. Poor and hot countries will always be easier to infect than rich and cold ones.

In order to get a 3 biohazard finish, you'll need to infect and eradicate humanity within 365 days--common requirement for mega-brutal scenarios. The cure progression, I think, varies among different plagues. The usual score needed for a 3 biohazard game has to be more than 65,000.

To give you an example, a game that finishes within 362 days with a cure progression of 31% will end with a score of 68,028.

Again, Guides posted here will work on normal games in mega-brutal difficulty.


Guides posted here will be categorized by country until such time that a strategy that works for most countries is found.

India Strategy

As the strategy names suggests, you want your pre-selected country to be India. If it's not keep quitting and starting a new scenario game until you get it.
If you're using this guide for a normal game, you know which country to start in.

Gene Setup:

  • ATP Boost
  • Aquacyte
  • Sympto-Stasis
  • Genetic Mimic
  • Extremophile
Tip: Devolve mutated symptoms that are lethal, but only do this on a maximum of three times. The mutation of Tier 1 symptoms such as vomiting, hyper sensitivity, etc. could be allowed.

1.) Make sure that you are started in India. Pop the red bubble and proceed to evolve the following symptoms:
  • Nausea
  • Cysts
  • Rashes
  • Abscesses
  • Coughing
  • Sneezing
  • Sweating
  • Skin Lesions
  • Pneumonia
  • Pulmonary Oedema
  • Diarrhoea
2.) Having the symptoms above will not only make infection faster, but will also make you earn slightly more from popping red bubbles. Continue by evolving the following in this order:
  • Water 1 & 2
  • Blood 1 & 2
  • Cold Resistance 1
  • Drug Resistance 1
  • Cold Resistance 2
  • Necrosis
  • Drug Resistance 2
3.) Having Necrosis at an early stage will somewhat hinder the effects of Genetic Drifts and provide both lethality and infectivity. To continue, evolve the following symptoms(order isn't necessary, but recommended):
  • Vomiting
  • Pulmonary Fibrosis
  • Hyper Sensitivity
  • Dysentery
  • Insomnia
  • Paranoia
  • Seizures
  • Insanity
  • Paralysis
  • Coma
  • *Genetic Hardening 1 & 2
*These abilities are optional, but will help you achieve a better score.

4.) Wait for the entire world to be infected. Over 80% of the world's population should be dead by the time the pop-up comes up. Once the pop-up saying "No one is healthy" shows up continue by:
  • Evolving every possible symptom. Start with the lethal ones first, namely: Total Organ Failure, Hemorrhagic Shock, Internal Hemorrhaging, Systemic Infection, and Tumours. Then the rest of the symptoms, if you want.
  • Remaining DNA should be used to evolve Genetic Re-Shuffles.

With the use of this strategy, I was able to obtain 3 biohazards in mega-brutal difficulty. I kept on starting a new game until India was selected for me. This strategy was only tested once in the scenario, but multiple times in a normal game.
-End of India Strategy-

If you have any strategies or tips for us, please post them at the comments below. Strategies which have been tried and tested by our team, or have been up-voted multiple times will be included along with this guide.


  1. The india guide works if you start in brazil as well

  2. I found tht if u click the country u want before u get rid of any of the beginning notifications two start buttons pop up and u can click the country u want to start with. Idk if the guide will work tho.

  3. This worked well for Balkan States. I just replaced Cold Resistance with Heat Resistance

  4. This guide simply does not work. Over 25 attempts. No better than 2 bio hazards. (Even lucking into an india start twice)rest of attempts from Saudi Arabia, China etc.