Plague Inc. Who Needs Brains Achievement Guide & Walkthrough

"Take humanity back to the stone age" pretty vague description for the 'Who needs brains' achievement, right? Well, this achievement can only be unlocked by finishing the Frozen Virus scenario in a certain way. Sheds some light on that description now, huh?

What do you need to do?

In order to unlock this achievement, you must turn the human race into neanderthals in the Frozen Virus Scenario. A unique symptom of the Frozen Virus lets you do this, Neanderthal Regression. But merely evolving this symptom won't be enough to unlock the achievement, you'll have to turn the entire human race into neanderthals thus "taking them back to the stone age" - description makes sense now.

To get this achievement, these pop-ups must show up:

 Now, I'm not entirely sure which of the pop-ups above unlocks the achievement, but usually these pop-ups show up one after the other - if you infect the entire world first, that is.

How to 'take humanity back to the stone age'?

Well, it just so happens that we already have a guide for this specific achievement.

Click here for a guide.

A few things to note:

1. The guide above is specifically made for mega-brutal difficulty. I'm not certain whether it is possible to unlock this achievement with other difficulties.
2. As of the 1.8.1(not sure, sorry) update, you will be unable to unlock achievements while cheat modes are active. In short, NO CHEATS.
3. Have fun and I hope this guide has helped you. Share your strategies or tips regarding this achievement with us, if you want.