What is the quickest way to kill everybody?

All the big 30-point symptoms near the center line are excellent at killing people off in job lots, although tricks like Pneumonia or Hypersensitivity can potentially be more effective in their specialized areas (As the descriptions state, Pneumonia is especially dangerous in cold areas while hypersensitivity is particularly dangerous in urban environments where exposure to various allergens is much more common).

I'm personally a fan of Coma because it also makes the disease harder to cure and Necrosis because it means that corpses still remain infective (which can be a big plus if you haven't infected everyone yet).

I personally usually go with these two in the middle here:

The two abilities are:

• Total Organ Failure
• Coma

I'm not sure if these are the fastest ways to kill off a population but between them they'll usually result in a world population graph that looks like this (assuming the whole population was infected before you went lethal):

This is a good method:

1. Wait until everybody is infected (a message will pop up saying "There are no healthy people left").

2. If you use a Bio-weapon, go to step 11,if not, go to the next step.

3. Evolve Coughing, Sneezing, Pulmonary Fibrosis and Total Organ Failure - this is your main symptom (you can devolve Coughing, Sneezing and Pulmonary Fibrosis for extra DNA points).

4. If cure progress is over 80%, go to step 6, else go to step 5.

5. You don't need to worry about the cure. Instead, evolve better symptoms:

   • Hemorrhagic Shock - very lethal (evolve Anaemia, Haemophilia and Internal Haemorrhaging)
   • Necrosis - very lethal (After Hemorrhagic Shock)
   • Tumours - doesn't increase severity, but is lethal (after Haemophilia)
   • Internal Haemorrhaging - quite lethal (after Haemophilia)
   • Systemic infection - quite lethal (after Tumours)
   • Immune Suppression - quite lethal (after Sneezing)
   • Dysentery - quite lethal (after Diarrhoea)

6. Get Insomnia and Paranoia (slows research).

7. Get Seizures (after Paranoia) and Insanity (after Seizures) - reverses cure efforts. Devolve Seizures if you want.

8. Get Coma and Paralysis - slightly lethal and reverses cure (after Total Organ Failure).

9. If the cure still builds up get Genetic Reshuffle in the Abilities section.

10. Get some of the good symptoms from step 5.

11. Get the Annihalation Genes (In Abilities) - Completely fills the Lethality bar (after all 3 of its main abilities).

12. Watch the world die!