Plague Inc. Bio-Weapon Normal Guide – Tips on How to Complete!

Plague Inc.’s Bio-Weapon plague type poses a unique challenge when compared to its siblings. Its closest comparison is the Nano-Virus, in that its key challenge isn’t flying under the radar but managing its unique traits.

In this case it’s the Bio-Weapon’s lethality, which gradually increases over time. You want to keep this as low as possible until the world is completely infected, then kick it into overdrive. We’re going to provide you with tips and tricks on how to do just that in this guide.

What is the Bio-Weapon?

A Bio-Weapon is a man-made virus that functions very much like a typical virus except for the fact that you are in complete control of how it functions. In Plague Inc. it’s a plague type that is accidentally released from a laboratory, and gradually increases in lethality over time, which poses unique challenges.

The more lethal a plague is, the faster humanity aims to discover a cure but you’re also at risk of countries shutting their borders completely, which can hamper your chances of infecting the entire planet.

Fortunately, you do have a unique trick up your sleeve with the Bio-Weapon, and that’s in its special abilities. Here’s how each of these work:

  • Gene Compression 1-3: Increases the time before lethality increases
  • Nucleic Acid Neutralization 1-3: Resets lethality to zero for several in-game days
  • Deactivated Modified Genes 1-3: Reduces lethality
  • Unlock Annihilate Gene: Significantly increases severity, infectivity, and lethality. This is basically your kill-switch, ending the game in a matter of in-game weeks.

As you can probably tell at this point, your first priority when playing this mode is in balancing growing your infectivity rate while also grabbing Gene Compression. We’ll go into full details later in this guide when we reach our full walkthrough.

How Does Bio-Weapon Differ in Terms of Gameplay?

Now that you understand how Bio-Weapon works, let’s take a look at how it differs in terms of gameplay. As we mentioned earlier, it’s very similar to Nano-Virus in that it has its own unique trait: lethality gradually increases over time. This puts pressure on you to infect the planet quickly, before countries start closing their borders.

So it suits a faster-paced gameplay style for those that like to think on their feet. You’ll spend your early game simultaneously managing the lethality while increasing infectivity. Once you’ve infected the entire planet, you can end the game incredibly quickly thanks to the special skill Unlock Annihilate Gene, which will have humanity on its knees in a matter of days.

While we’re not going to cover a speed run in this guide, this plague type is ideal for speed runners as the rate at which you can wipe out humanity is absolutely insane. It does require very careful management though, so you will have to be organised.

Bio-Weapon Normal Strategy

Bio-Weapon took us a good few goes to get right. The key challenge is managing that lethality, which starts to spike really early on, and has countries shutting their borders quickly. You’ll also find that humanity focuses on a cure rate a lot faster than normal, and progress can spike almost as fast as lethality if you don’t manage it.

However, we have settled on a strategy that worked for us every single time. We’ll give you a rundown of the general things you should be working on at each moment, but you will need to think on the fly, as this type of plague in particular takes on a bit of a life of its own.

  1. Start in a central rich country. We chose Spain, as it gives us Heat Resistance and spreads throughout Europe and Africa quite quickly.
  2. Control lethality. Get Gene Compression 1, 2, and 3. They’re incredibly cheap and will drastically slow down the rate at which lethality increases. This is absolutely essential early on, so start here.
  3. Increase infectivity. The next step is to start spreading the virus, so get Air 1 and 2, Water 1 and 2, and Extreme Bioaerosol. That will start it spreading nicely.
  4. While purchasing the infectious traits, you’ll want to keep an eye on lethality. Grab Deactivated Modified Genes 1, 2, and 3 – but not all at once. They work in a similar manner to Genetic Reshuffle but for lethality. Whenever you see lethality start to grow, grab 1 tier of these to bring it back a bit.
  5. Get Drug Resistance 1 and 2, Cold Resistance 1 and 2, and Heat Resistance 1 while managing lethality. You really don’t want this to pick up steam, as humanity will start to speed up a cure.
  6. Watch as the planet gets entirely infected. Slow down lethality by grabbing all three tiers of Nucleic Acid Neutralization and slow down the cure by grabbing Genetic Hardening and Genetic Reshuffle.
  7. As soon as the entire planet is infected, grab Unlock Annihilate Gene. Provided that the cure isn’t at around 90%, this will end the game before humanity has a chance to recover. You don’t even need to bother with symptoms, as this will max out lethality.

General Bio-Weapon Tips

  • DNA points are in short supply with this plague type, as you constantly have to spend them on managing lethality and cure progress. Be careful not to overspend – if you can.
  • You simply can’t fly under the radar with this plague type, as lethality grows relentlessly. Instead, you just have to manage the progress at which humanity focuses on a cure, and that’s down to the previous point.
  • We would recommend devolving every single symptom that mutates. Not only do you not need symptoms thanks to Unlock Annihilate Gene, but you really don’t want anything increasing severity or lethality, as keeping them down is hard enough.
  • Certain countries will shut down their borders – it’s unavoidable with this mode. Instead, just make sure the virus has spread before your starting country closes its borders. You should be fine if this is the case.
  • As with our other guides, you can devolve all transmissions and resistances as soon as the entire world is infected. You’ll probably have to do this to afford Unlock Annihilate Gene.
  • Once you’ve got Unlock Annihilate Gene you’ll start to receive a ton of DNA points from killing off the world’s population. Spend these on slowing down the cure effort. There’s no point grabbing symptoms as lethality maxes out anyway.
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  1. I hate the bio-weapon in plague inc. They’re hard and they kill people already when your about to infect the countries. I can’t even save enough DNA points to use them for evolution.

  2. Thanks for your guides. I followed them and beat the game. The game has a lot of obscure options and little info about the countries themselves, so it can be quite confusing to work out what is important and what is not, despite the game being around for many years, the devs haven’t really improved it. Yet, it’s quite fun and in some ways thought provoking.