In Plague Inc. for the Android & iOS (iPhone, iPad, iPod Touch, etc.), Virus is the second plague you have access to.
Virus can be a little rough at first, primarily because it mutates quickly, making it hard and expensive to control. The main strategy is to keep the symptoms in check in the beginning, and then unleash hell at the end.
Viral Instability is the special Virus Ability, and it increases symptom mutations. This can be a double edged sword, as it can literally give you a ton of free symptoms, but you have to keep the lethal symptoms in check for a while. Devolving the lethal symptoms can still be cheaper than purchasing symptoms though.
It may help to beat Bacteria a few times to unlock some of the gene modifiers. Genes like ATP Boost give you some bonus DNA at the beginning of the game, which can give you a nice starting advantage. Anything you can unlock will most likely give you a nice edge against the upcoming plague types.
Stage 1
- Start in China
- Abilities: Drug Resistance 1, Viral Instability 1
- Transmissions: Air 1, Water 1
- Symptoms: Let your Viral Instability get to work, purchase Rash and Sweating if they don’t mutate, devolve any lethal symptoms mutated
Stage 2
- Abilities: Viral Instability 2, Genetic Hardening 1
- Transmissions: Air 2, Water 2, Extreme Bioaerosol
- Symptoms: Let your Viral Instability grow symptoms, buy Coughing, Sneezing, Skin Lesions if they don’t mutate, devolve any lethal symptoms mutated
Stage 3
- Once China gets around 1.2 billion infected, they will be alarmed and countries will start to fund the cure
- Abilities: Viral Instability 3, Genetic Hardening 2 as the cure starts to build
- Symptoms: Let your Viral Instability grow symptoms, buy Cysts and Hyper Sensitivity if they don’t mutate, devolve severely lethal symptoms mutated
- Transmissions: Bird 1 and 2, Livestock 1, Blood 1
- Save about 30 to 40 points for the next phase
- Most countries will be infected, around 4 billion of the population
- Symptoms: Immune Supression, Paralysis, Coma (both Paralysis and Coma slow down cure research), only devolve severely lethal symptoms mutated
- Transmissions: Start building onto Livestock 2, Rat 1 as needed
- Abilities: Cold 1 and Heat 1 if you have extra points and need more infectivity, Genetic Reshuffles if the cure starts to get out of hand
Stage 5
- All countries infected, around 5 to 6 billion of the population
- Abilities: Genetic Reshuffles if the cure gets too high
- Symptoms: Slowly build up Total Organ Failure, Necrosis, Hemorrhagic Shock, Internal Hemorrhaging, you don’t want to outpace kill rate with infection rate  in the last countries infected
- Transmissions: Only if you have extra points
Stage 6
- Everyone is infected, time to destroy them
- Abilities: Genetic Reshuffles if the cure gets too high
- Symptoms: Throw whatever lethal symptoms at them you can
- Congrats, you win!
