What Comes After: The Infected
Alright, here we go! It's gonna be long and some of this stuff may change some depending on how writing goes, but it should all mostly stay the same!
The Pathogen
To start, let's go with the pathogen itself and what it does. So, the first iteration of the pathogen takes roughly two months to settle in and change it's host (this will change depending on which strain Uninfected contract and people's individual bodies). After being infected, the pathogen quickly goes to work growing in number while damaging as few cells as possible (which leaves those infected asymptomatic for anywhere from a week to nearly a month). However, once it has colonized the major organs (especially the brain), it begins causing minute mutations in the host's cells and their very DNA. This is why many infected become sick very quickly; their bodies are trying to adapt or fight what the pathogen is doing, but it doesn't work.
Now, what types of mutations someone receives changes based largely on their hormones, their bodily condition, and a few other factors. We'll get into all that later though, as we move through each type of Infected. The spread of the pathogen is through most bodily fluids and has a spread rate of over 90%.
The Infected
Now we'll look at each type of Infected. *All Infected have a sensitivity to light and can tell an Infected from an Uninfected.
Stage 1: Meatheads
Is one of the types of Infected called Meatheads? Yes. These types of Infected are caused by high levels of testosterone and happens in those who are either physically fit or leaning towards physically fit. They crave high amounts of protein, calcium, sodium, and water. Over around a 6+ month period, they will steadily face these types of changes:
Massive amounts of muscle growth. They are incredibly strong and resilient and will be one of the harder to kill Infected...
...But they also suffer the most brain degrading from the fever the pathogen causes. Meaning... they're pretty stupid.
Stupid don't mean easy to kill; along with their muscle growth, they begin packing on bone growth to their skulls, resulting in knobby growths under their skin. This also means it takes a good sized bullet to be able to make it through to kill them and knives/blades aren't going to do you any good unless you try to decapitate them.
They will eventually become unable to see well, relying more on their other senses instead.
They steadily become highly aggressive to everything that's not a fellow Infected... and sometimes even them.
Stage 1: Stalkers
Stalkers tend to have higher amounts of estrogen, but not always. They can range in physical form, and are one of the less common types of Infected. Their changes and attributes:
Stalkers are given their name for the fact that if they spot a group of humans, they will follow them for a time and then begin to loudly shriek for other Infected to come. It has been the undoing of many early camps and settlements.
These Infected have varying degrees of brain degradation, but tend to have lesser amounts than the other Infected. This allows them to still have some strategic and critical thinking even after years of Infection, and some can even speak.
Stalkers will start growing bone spurts along their fingers, that eventually turn into spiked or clubby extensions from their hands. This causes much issue with using their hands, some being unable to after a certain point. However, they are very aware of how to use this to their advantage in fights.
A very slim few Stalkers are able to think clearly enough to round up other Infected and launch attacks against human encampments.
Fighters
Fighters are a catch-all for the Infected who aren't anomalous and also don't fall in under Meatheads or Stalkers. Fighters tend to have a few separate categories: Fast, Bloaters, and Other.
Fast: Fast Fighters have evolved to be incredibly agile (like Annette in Chapter 2). They are usually on the slimmer side. They strike fast and hard, lashing out or trying to knock over their prey. However, they have weaker bones than other Infected, which can be used to your advantage. They are even more aggressive than Meatheads.
Bloaters: Bloaters are as it sounds: Infected with severe gaseous bloating. Some people's bodies react poorly to their newfound mutations, leading to a large build up of gases in their bodies... which will eventually make them explode. Did I mention the gases are flammable?
Other: The rest of the Fighter group. These tend to be individuals with varying body types and hormone levels, but all carry a similar type of mutations, albeit some being unique: increased strength and agility; superior senses; aggression.
Stage 2: Hulks (Meatheads, but Even Worse)
At any point beyond a year of being Infected, a Meathead who has ample supply of protein and calcium may suddenly be hit with a new wave of mutations, this time causing their bones to elongate and become denser, and even larger amounts of muscle growth... which eventually leaves them to become a Hulk, which can be 8+ feet tall and a wrecking ball of mass destruction. Thankfully, they're quite rare. About them:
They are nearly completely blind. Their eyes are highly sensitive to light, so if you get some flares you can definitely hurt it long enough to figure out how the hell you're gonna kill it.
Their strength is... incredible. Concrete, brick, even solid steel can do next to nothing to protect against it. You know how George in Rampage started wrecking shit? Yeah. Yeah.
Unless you're packing bullets that blow the limbs off of people, you're probably not going to be able to kill this thing with a bullet to the head. Those boney growths on Meatheads? Yeah, Hulks' skulls are nearly impenetrable at this point due to the sheer thickness of their skull.
Stage 2: Reavers (Stalkers Become Your Worst Apocalyptic Nightmare)
Reavers are the rarest type of Infected, and only form from Stalkers who still have high amounts of brain function left. In fact? The pathogen starts restoring brain functionality on these bad boys. A Reaver takes at LEAST two years to come into being, usually longer, and the longer it takes, the smarter it is. Now, about them:
Reavers are incredibly smart, able to plan well-thoughtout attacks on settlements and encampments. They release a pheremone that draws Infected to them, allowing them to amass an actual army of the things.
All Reavers can speak and understand language. In fact, they can carry on very complex conversation. However, this does not change the fact it knows you're human. Nor the fact it wants you turned or dead; it's way or the highway, you dig?
The bony spurts on a Stalkers' fingers have been carefully turned into sharp spikes on the Reaver; they take excellent care of them, and are intimately aware on how to use them.
Reavers also have elongated limbs. They also have a heightened control of their body, allowing them to pretty much nearly slither across the ground unnoticed by its prey... until it's too late.
The Stalkers' shriek has turn into a near banshee-like unearthly wailing the Reaver does, which is so loud it carries over a very large stretch of space. If you don't shit your pants hearing it, you probably will when the ground begins to rumble with the sheer amount of Infected storming your way.
Lastly, Reavers are the only ones who may don armor. Does this mean some of them carefully carve up a bucket and put it on their head? Yes.
Anomalous Infected
This category is for all other Infected, which are very unique to themselves mostly; some anomalies can occur a few times, but in general, they are very different from one another. They have varying types of mutations, many of which can be debilitating for it, others, to you (does that mean some have near-venomous spit? Unfortunately for you, yes. The human mouth is filthy but theirs is an actual cesspit).
Thank you for coming to my TedTalk. The most common Infected is the Fighter category, and well technically anomalies too I guess. More types may be added later, but these are the ones I have for now! But, one last thing...
There is three types of humans: Uninfected, Resistants, and Immunes. Uninfected are normal people who have just not been exposed to the disease/have been exposed but didn't contract it out of sheer luck, and make up the majority of the population; Resistants are people with varying degrees of resistance to the pathogen, meaning they can even survive a few full-on bites at once or accidental ingestion of small amounts of Infected blood and either become sick but not turn or not become sick at all; and Immunes are people who are completely immune to the pathogen, and no matter the amount of bites they receive nor exposure to the pathogen, they will not turn... unless they meet a certain condition, one you may see in book 3 or later. ;-)