Sorry for the bad formatting.
Important Notes: In case you didn't know, getting severity will increase the dna you get from bubbles.
If I tell you evolve a symptom/transmission and it has already mutated, skip that instruction.
If Greenland/Iceland or some other island country's ports close, quit the game and restart this. I estimate this guide has a 70% success chance.
The thing that makes virus different from the other diseases is the high mutation rate and the cost to devolve. We want to utilize the pros of each plague and try to reduce the cons of the plague. We will do this by using the base oxidization gene (THIS IS ESSENTIAL.) The base oxidization gene lets you mutate transmissions in addition to symptoms and makes it easier to cure. I find this an extremely fair trade-off for getting a ton of free transmissions. The best thing about base oxidization is that mutating transmissions increases mutation chance (well most of them.) We want the ATP boost for a head start. The environment genes is your choice, though I prefer extremophile. In virus, we want to evolve a lot of symptoms. We don't need to focus on transmissions because we will mutate
them. The symptostasis gene lets us evolve symptoms without increasing their cost (normally whenever you evolve a transmission/symptom/ability, the cost of all the other transmissions/symptoms/abilities increase.) This will let us evolve a lot of symptoms (SYMPTOSTASIS IS ALSO ESSENTIAL.) Last but not least, we want the aquacyte gene. This will help with reaching the troublesome, cold countries as we will be starting in India. We might end up with unwanted symptoms. If you mutate total organ failure or hemohragic shock, devolve it. Otherwise you shouldn't.
We start with cysts, abscesses and hyper sensitivity. This gives us a good early boost. Then we get rash and sweating into skin lesions which gives us a huge spike in infectivity. Then we get coughing,
sneezing, pneumonia, nausea, vomiting, insomnia, paranoia, anaemia, haemophilia, diarrhea, pulmonary odema/fibrosis for the infectivity and severity. Don't worry if your disease gets discovered early, it should.
I am aware of the fact that you are getting lethality. In mega brutal, they added
genetic shift which increases the DNA costs of transmissions/symptoms/abilities bass on how many
people are infected. The more infected, the higher the cost. In fact, at the whole population infected, total organ failure costs 60 DNA! This is clearly unacceptable. We will need to get lethality earlier.
Then we get water 1/2, drug resistance 1, cold resist 1 and viral instability 1. Then we get air 1/2, cold 2, extreme bioaersol, genetic hardening 2 and drug resistance 2. At this point this starts getting a bit risky. We evolve necrosis, dysentery, insanity and systemic infection for the infectivity, severity
and lethality. At this point we wait for every country to become infected. If your DNA total gets
above 125, evolve a transmission of your choice. Once every country is fully infected or close to full, evolve total organ failure, hemohragic shock and internal hemorrhage. Once the world population
gets below 1,000,000,000 evolve genetic hardening 1/2/3 for reducing the cure percentage and increasing your score. Use your remaining DNA to evolve some symptoms to speed up the demise of the world. You should end up winning in about 300-350 days and about 10% cure. This should result in about 400,000 points.
I hope this guide helped you. :)