It’d be nice if the alien worms, once shot at, would respond by digging underground and then emerging elsewhere. (Or at least a mutated form of them, it seems like a smart way for them to evolve via the mutation system).
Another idea could be that when shot, they have the possibility to split into two weaker halves.
You could have a sharp toothed armoured worm which is a melee specialist.
If not that, maybe a rocket launcher on it’s back? 
You let loose your imagination. Those are lesser forms of creature. You want mutate them?
Could have a HP increase ahead of that, maybe they evolve to burrow if they tend to get wounded before they are killed, or evolve to split if they tend to get blown away in one hit?
(Only say that as the evolution is supposed to be influenced by player tactics, I think?)
Yeah, why not, it’s such a great mechanic, I’d like to see everything have the possibility.
How does it work in nature? Does the more simple life-form mutate quicker, or the more complex? Or is it more to do with life-span regardless of complexity? - Bacteria as an example are known to evolve very quickly, but then so are dogs (with directed human intervention).
worms could also have a chance to go ka-boom instantly whenever flung by a chiron (like fire worms go splat and set fire to…a lot…lol)
frag worms that send bone shards in a big radius, cause lower bamage but cause bleeding (without the need to disable a body part)
“Misty The Worm” - generates a very small patch of misty upon being splatered or splatering after being chiron-launched…
Simpler does - the bacteria/dogs comparison isn’t so much a question of size, but natural selection vs. selective breeding.
Natural selection is a lot slower, but has the advantage of finding the most efficient response to the environment. Selective breeding is much accelerated, but you end up with genetic problems, like noses you can’t breathe through (pugs), hips that dislocate all the time (rottweilers).
The words evolve and mutate seem to get used fairly interchangeably in fiction, because “mutate” sounds cool, which is great, but can get confusing when looking things up in real life. An individual organism can mutate, but that mutation can impede its ability to reach reproductive maturity. The species as a whole evolves - a later specimen can be said to be “more evolved” than an earlier one, which is where it can get mixed up.
Hope that makes sense? 
TL;DR
Small organisms evolve faster.
Mutation = Changes to an organism’s genes.
Evolution = Changes to a species over time
Natural selection = Naturally occurring process which drives evolution
Selective breeding = Making all the pretty dogs mate so that their kids have a weird face
Cheers for the explanation, that’s much appreciated 
So am I right in thinking that GM crops would be classed as a mutation?
And I guess, the actual question should be, is it easier to cause mutation in a smaller or larger organism?
So I’ve just dipped back in to the forums, having had some time away from the game, waiting for some updates to drop. Plus that itch.io racial equality bundle has had my wife and me chomping through bizarre indie games for a good while now. That worm idea still sounds neat, as they don’t have any mutations as far as I’m aware (having not completed my most recent play-through yet).
Also, to answer your question months later - GM crops would not always be an example of a mutation, it depends on how the genes were modified. Historically, (like, thousands of years) humans have indirectly modified crop genes through selective breeding, or domestication. So, although you’re changing the species over time, you’re not directly causing a mutation. It’s a slow process, but it eventually gets there.
In more recent history (tens of years), we’ve used direct gene editing. In some cases this involved inducing mutation by exposing cells to mutagens (like UV light, or ionising radiation like x-rays or gamma rays, or certain chemicals), looking for a useful mutation, and then growing crops from that edited cell.
Even more recently, tools (like CRISPR) allow us to target a specific mutation and drop it in. So, instead of rolling the dice and waiting for the result we’re looking for, we can just target gene sequences specifically. Yay!
It’s like selective breeding is mixing yellow and blue paint for generations, until you get the shade of green you’re looking for. Genetic engineering is like putting a single fleck of the paint’s pigment under a microscope, and altering its chemical make-up until it absorbs exactly the wavelength of light you need it to to achieve the shade you’re looking for, and then making a whole new paint based on that. At the end or either process, you’ve got a pot of paint in the shade of green you’re looking for, but one is more accurate, and required fewer steps to get there.
Oh! That does give me pause, as regards the world of the Pandoravirus.
What if Pandorans had bad evolutions sometimes? Or they could be induced?
So, one of the problems with traditional domestication, is the lack of biodiversity - it can make a biome vulnerable to disease (see the Great Hunger in 19th century Ireland).
You wouldn’t think Pandorans have that problem, as they evolve so quickly, but they do so uniformly. As they’re reacting to their environment, albeit very quickly, it’s possible that you’d see unintended consequences. Like, perhaps they’d evolve great leg armour, but the gene that’s creating this reinforced chitinous shell is also stripping calcium phosphate out of the creatures bones, so the armour on their legs goes up, but the limb HP goes down.
Or, maybe it does something else unrelated, like it impedes clotting, so they take increased bleed damage when that limb is disabled.
Probably a bit much lore-wise at this stage, but maybe if Phoenix forces could introduce a genetic weapon to a… I dunno, flying enemy as a transmission vector? 
Unintended Mutations could totally be a thing.