Plague Inc: Evolved – Necroa Virus / Guaranteed Victory

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Comprehensive walkthrough for players struggling with the Necroa Virus on normal difficulty. Includes easy to follow step by step instructions, strategy break downs, DNA point costs, and side notes. This method has been tested numerous times by the author and has a 100% success rate if done properly.

Getting Started

This is a walkthrough for anyone that is having difficulty passing the Necroa Virus stage. I’ve run this strategy numerous times and have a 100% win record with it. I’m fairly confident this strategy will work for anyone that is having difficulty moving beyond this plague. If you follow these simple steps then victory is almost certain. Let’s get started.

First, I’ll explain the genetic code modifiers I used and why. The only modifier that you absolutely need for this strategy is Creationist. The others are meant to help speed up your game.

Modify Genetic Code:

  • ATP Boost
  • Creationist
  • Aquacyte
  • Extremophile
  • Spliced Activation

1. The first skill I chose was ATP Boost. The reason for that was to evolve my first mutation immediately.

2. Creationist is by far the most important modifier to use for this strategy. If you don’t have it unlocked yet you’ll need to get it because it is absolutely necessary. I suggest playing on Virus to get some quick victories until you unlock it.

Creationist is important because it will minimize the need to devolve mutations. Once a symptom mutation occurs it will cause the world to begin searching for a cure (if left unchecked) and then it’s a race against time. That’s why it’s important to avoid symptoms until you’re properly set up. I’ll go into further detail during the gameplay walkthrough.

3. I use Aquacyte because it increases the chance to infect island countries that only use seaports like Greenland, the Philippines, and the Caribbean.

4. I use Extremophile because it gives a bonus in all types of environments. If you don’t have Extremophile unlocked then the next best option to use is Hydrophile. Neither of these modifiers are necessary for victory. I simply use them to speed up the infection rate.

5. If you haven’t unlocked the Necroa Virus genetic modifiers yet that’s okay. This strategy doesn’t need them. Spliced Activation is used mainly as an “Oh, sh*t!” buffer if your zombies are having trouble with Z Com or if you want to use extra DNA near the end to boost your horde numbers and finish a little faster.

With that being said let’s move on.

Starting Location: India

India is a prime starting location that has a high population and ample conditions for virus growth. It has an airport and seaport, and is connected by land to numerous other countries. India’s airport and seaport go to a wide variety of countries and continents as well. You don’t have to start here, but it’s a good idea for the sake of this walkthrough and the specific modifiers that I’ve chosen.

Zombie Preparation

Step 1: Select Saliva 1 from the Transmission tab

Once you’ve selected India you should be able to immediately select your first mutation thanks to the ATP Boost modifier. If not then just wait a couple of seconds. Either way, you won’t have to wait long until you have enough points to evolve your first mutation.

Cost: 6 DNA points

Step 2: Select Saliva 2 from the Transmission tab

This is needed to unlock the Water transmission mutation.

Cost: 6 DNA points

Step 3: Select Water 1 from the Transmission tab

This mutation is why you want to start in a country like India, because it is a humid country with a seaport. This will speed up the infection rate of your virus nicely.

Cost: 7 DNA points

Step 4: Select Water 2 from the Transmission tab

This is critical for getting the infection rate as high as possible in seaports. It also helps speed up the infectivity in humid countries.

Cost: 14 DNA points

Step 5: Select Gastrointestinal Expansion from the Transmission tab

This will be the last skill that you’ll select from the Transmission section. It gives a nice boost to your infectivity so be sure to pick it up before moving on to Abilities.

Cost: 12 DNA points

Step 6: Select Drug Resistance 1 from the Abilities tab

By the time you’ve moved to Abilities you’ll be close to infecting rich areas like the USA, UK, and Australia. This will help prevent your virus infectivity rate from stalling do to medicines.

Cost: 9 DNA points

Step 7 & 8: Select Cold Resistance 1 & 2 from the Abilities tab

You’ll want to put points into these next to help your virus spread in cold countries like Greenland and Canada. If you follow this walkthrough you’ll more than likely have Z Com’s HQ in Canada so cold resistance is important.

CR 1 cost: 6 points
 CR 2 cost: 9 points

Step 9: Collect DNA points and wait

At this point all you need to do is pop bubbles and let your infection spread across the world; however there are some things that you’ll want to pay attention to during this time.

The most important thing to be aware of is virus mutations. If you get a random mutation that causes a symptom you need to devolve it immediately. You might have to deal with this during your run or you might not. Usually I didn’t have to devolve a random symptom but occasionally I had to because some countries needed more time to get a higher infected populace. You should have more than enough DNA points to devolve a random symptom mutation if one occurs so it’s nothing to stress over.

The other thing to be mindful of during this time is where the infection has spread. This has to do with when Z Com establishes an HQ. If you follow this formula it usually will be in Canada but I have had them establish HQs in a couple of different countries. That was mainly caused by the percentage of infected people per country.

When I waited for the entire world to get 100% infected before I evolved symptom mutations Z Com would randomly spawn somewhere; however if I began to create zombies before Canada was significantly infected then Z Com always ended up being in Canada. I think the reason for this is because Canada has the best medicine in the game so they were the slowest to get infected, but I’m not certain. I found anywhere between 3-5 million infected people in Canada to be a good number before moving forward.


It’s important to note here that when you start mutating symptoms the country with the lowest amount of infected citizens is generally selected for Z Com’s HQ. Be sure to take a look at the map and get an idea for where you may be fighting near the end.

Also, be sure to double check your World tab to make sure that every country has been infected before proceeding. Once you start the symptom mutations it’s like a domino effect. Countries will shut down their airports, seaports and borders quickly. It sucks missing a single country and having to restart. I know from experience.

Zombie Assault

Step 10: Select Insomnia from the Symptoms tab

Once you have enough points (55-72 give or take) you’re ready to begin the next phase. I start on the left side of the Symptoms tab with Insomnia. The reason for that is because it’s cheaper to evolve and it slows down research speed. It’s a double whammy and a good way to go. From here on out you’ll need to evolve mutations as soon as you have the points. Quick evolution is key.

Cost: 5 DNA points

Step 11: Select Fever from the Symptoms tab

This slows research speed and is on the way to unlocking your zombie horde.

Cost: 6 DNA points

Step 12: Select Photophobia from the Symptoms tab

Same reasons as before. You’re increasing infectivity and severity while slowing down research.

Cost: 3 DNA points

Step 13: Select Delirium from the Symptoms tab

This increases all 3 stats and goes to unlocking zombies.

Cost: 15 DNA points

Step 14: Select Cytopathic Reanimation from the Symptoms tab

Now you have your zombie horde.

Cost: 15 DNA points

Step 15: Select Anaerobic Resuscitation from the Symptoms tab

Increases lethality and severity.

Cost: 14 DNA points

Step 16: Select Enhanced Motor Control from the Symptoms tab

Increases severity of your horde and makes them harder to kill. At this stage you might have to wait and gather more DNA points before you’re able to evolve your next mutation. Regardless, continue on once you have enough points.

Cost: 9 DNA points


From here on you’ll be waiting short periods between mutations to gather more DNA. Pop bubbles, pay attention to your point total, and evolve mutations as needed.

Step 17: Select Peptide Surge from the Symptoms tab

Severity increase.

Cost: 13 DNA points

Step 18: Select Acidic Reflux from the Symptoms tab

Severity increase.

Cost: 17 DNA points

Step 19: Select Naja Mortis from the Symptoms tab

Increase to severity and combat advantage.

Cost: 25 DNA points

Step 20: Select Autothysis from the Symptoms tab

Increase to severity and combat advantage. Now it’s time to move back to the Abilities tab.

Cost: 32 DNA points.

Step 21: Select Horde Instinct from the Abilities tab

This is to unlock the mutations that increase horde sizes and quickly overwhelm the rest of the infected humans.

Cost: 6 DNA points

Step 22: Select Horde Mentality from the Abilities tab

This increases your horde size into the thousands.

Cost: 9 DNA points

Step 23: Select Horde Vocalisation from the Abilities tab

This increases your horde size into the hundreds of thousands.

Cost: 15 DNA points

Step 24: Select Horde Pheromones from the Abilities tab

This increases your horde size into the millions.

Cost: 21 DNA points

Step 25: Select Regenerative Activation from the Abilities tab

You’re going to want to invest points into this category to use the Active Abilities on the world map. Remember what I was saying about having an “Oh, sh*t!” buffer for Z Com? This is where that comes into play. If your zombies are struggling this can be used to turn the tide quickly, or you can put the boots (and bites) to Z Com.

Cost: 10 DNA points

Step 26: Select Regenerative Bio-synthesis from the Abilities tab

Cost: 11 DNA points

Step 27: Select Epidermal Digestion from the Abilities tab

Cost: 12 DNA points

Step 28: Select Cranial Metastasis from the Abilities tab

Cost: 14 DNA points

Step 29: Select Ambush Predation from the Abilities tab

Cost: 13 DNA points

Step 30: Monitor zombie horde

At this stage you should be nearly finished destroying the world’s population with a few DNA points to spare. Canada will more than likely be the last country standing against your zombie horde. If not then whatever country Z Com ended up basing their HQ in is where you’ll want to focus your attention.

I usually use the Regenerative Activation (zombie hand Active Ability) to add more zombies for Z Com to deal with and speed up the takeover. If you used the Spliced Activation modifier then you’ll have a nice discount when using that skill as well.


That’s all there is to it! All in all this strategy should take roughly ten minutes or so to complete. If you’ve made it this far then you shouldn’t have had any major problems getting your first victory with the Necroa Virus. All you need to do is repeat the same process if you want to unlock the rest of the zombie modifiers. Four more quick campaigns and you’re finished.

Volodymyr Azimoff
About Volodymyr Azimoff 13378 Articles
I love games and I live games. Video games are my passion, my hobby and my job. My experience with games started back in 1994 with the Metal Mutant game on ZX Spectrum computer. And since then, I’ve been playing on anything from consoles, to mobile devices. My first official job in the game industry started back in 2005, and I'm still doing what I love to do.


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