Plague Inc. On the Naughty List Achievement Guide

Been lazy, gluttonous, jealous, or intoxicated lately? Then you're probably on the naught list. Sorry. The "On the Naughty List" achievement forces you to evolve black-icon symptoms that will make Neurax-Santa put humanity on its naughty list. You do not want that. You must always be the ideal human for the worm. ALWAYS.

All I'm really sure about the naughty combo this achievement wants you to get is to evolve Sloth, Gluttony, Jealousy, and Intoxication. These are all at symptoms exclusive to the Santa's little helper scenario, like this achievement if you haven't already guessed. The first three will be unlocked in order after you evolve Festive Tendrils, Intoxication, on the other hand, requires you to evolve Indulgence and Partying first--makes sense, indulging and partying does lead to intoxication. Damn, I'm smart.

It's always best to attempt getting this combo in Casual difficulty, unless you're a real man and want a challenge then go for it on mega-brutal. No one's stopping you.

I have experimented with this quite a bit and found out a few things:

1. Evolve all the black-icon symptoms, namely Sloth, Gluttony, Jealousy, and Intoxication. I like repeating myself.
2. Evolving the black symptoms alone will not let you activate the naughty combo. I tried, nothing happened, wasted a considerable amount of time.
3. Try evolving every single symptom in the symptom tree, it works. Works best when you don't evolve the red-icon symptoms. Those are for good humans, we're being naughty remember?
4. Want a more descriptive and factual guide? Try Google.

The amount of information I have given you is enough. If you're still having trouble understanding, here's a screenshot of the stuff I evolved when I got the pop-up. Yay! Pictures!

As you can see, I have also devolved Indulgence and Partying just to be sure. The other stuff are just there for...stuff.

Seriously, though, having only those symptoms will help you activate the pop-up and unlock the achievement. You'll have to wait for some time, but eventually this pop-up appears, along with the achievement:

Guess I'll be getting a Lump of coal this year. ALL PRAISE THE WORM!

Thanks for reading, guys. Hope this unreliable guide has helped you get the achievement and as always, Happy Spicy Gaming!