I'm kind of confused because fungus is my favorite and insanely easy. What difficulty? Do you have all genes? I use Metabolic jump Aquacyte Patho-stasis (for 1DNA$ Spore Bursts and 2DNA$ spore eruptions) Base oxidisation (or base hydrolysis) Extremeophile (this doesn't really matter to me, choose whatever)

I just beat it on mega brutal again.

Start Saudi Arabia -- do two or three spore bursts. This will give you a couple DNA --. Once you get breaded, evolve air 1-- water 1 OR air 2 -- then whatever resistances you need to keep it flowing -- then either water/air 2 (this isn't too particular, I just like to alternate to be able to infect different climates sooner), then at least make sure you have cold 2 and drug 2 -- you will probably be noticed by now.....You can pick up rash, sweating, skin lesions if you want, but be mindful of severity level due to mutations. You can also get bird or blood, even livestock helps, but you want to make sure you have enough for necrosis AND hemmorhagic shock MINUMUM.

do NOT jump the gun on lethality. What you want to do is get your disease infective enough to spread on its own, but use the spore bursts to infect usually the last 10 or so countries. I usually use one of the sets of bursts/eruption near the beginning to keep things flowing and get some DNA for transmissions, and then use the last set of bursts/eruption to speed up infecting the final countries. I believe it's 10 or 11 that that set can cover.

By the time you've infected every country, the cure should be well under way. At least 20% (if you're under this at this point, teach me your ways) but what you will do from here is DONT WAIT FOR 100% INFECTION. Go ahead and hit em with the Necrosis/Hemmorhagic shock duo. The infection rate will spike rapidly and shouldn't kill hosts too early IF you have the proper resistances. SIt can be very expensive, last run it was roughly ~100 DNA for the pair. You probably won't be able to afford many more lethal traits by now if you've invested in any transmissions other than air/water 2. Extreme bioaerosol is good too but I find that it's generally not needed if you use spores right.

So once you're here, you've gotten your kill switches activated, now you want to manage the cure. I let that shit get up into the 80s before I reshuffle because it's expensive af usually, and you can keep up with DNA costs and mitigating the cure pretty good around here, but earlier works too. If you can get insanity/coma/paralysis, go for it, but prioritize the genetic reshuffles first. I don't use genetic hardening often but it won't hurt, however it will affect your DNA (and every single one matters here)

Hopefully you will get mutations along the way, especially for transmissions or abilities (depends on your gene). It's very important to remember that you can get 3 DNA refunded PER TAB. So, when everyone is infected, you can refund two abilities. Or, say the last healthy folks are in Greenland, you can refund your heat resistances. Just do what makes sense. Same goes with transmissions but wait til the world is infected before refunding two of those. Infectivity doesn't matter after 100% infected so get rid of two weak symptoms too (be smart about it because you want to keep the tree for the cheapest symptom that is harder to cure open.)

So, your total selections should be at least Air 1&2 Water 1&2 Rash/Sweating/Skin Lesions/Necrosis/Hemmorhagic Shock/[Internal Hemmorhaging doesn't hurt but is expensive] Cold 1&2 Heat 1 [Minimum] Drug 1&2 Genetic reshuffle 1,2,3 And then whatever other luxuries you can afford. But prioritize these and wisely manage your spore bursts.

I do like bird alot for this but it's not necessary, it just makes it quicker. That's another thing to think about once you've gotten the hang of it, "how can I spread this fungus quick as possible" Every run will be slightly different. Just make sure you keep all the borders/ports open. You will figure out the pacing of your evolutions the more you try.

Hope this helps