Bonus images related to THIS POST.
First pic represents the absolute largest Leon's monster form gets, I think. Any bigger than this and he's starting to lean kaiju.
And then reposing my "monsterfucker litmus test" pic separately because why not.

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Bonus images related to THIS POST.
First pic represents the absolute largest Leon's monster form gets, I think. Any bigger than this and he's starting to lean kaiju.
And then reposing my "monsterfucker litmus test" pic separately because why not.
[Mutation AU]
Leon S. Kennedy's theoretical final form, with a Luis for scale.
It's kind of painful initially, and he's afraid he won't be able to come back for this, but a few fights maybe merit Leon achieving a nearly-full or full transformation. I think Krauser (rematch) might be one, or Saddler.
And, uh, the final boss fight of RE9, but Leon loses the ability TO alter the expression of his mutations for the latter half of 9.
In the events of 4- the state of his plaga is progressing too rapidly for it to be safe to use Luis's machine to kill it. He seems to have full control of himself, so they can only hope that he won't die/lose his mind when Saddler [and the Queen plaga] are killed.
He doesn't. Later study reveals that the cocktail of latent/mutated/suppressed T- and G- virus in Leon's body are eating the plaga alive, mutating it and rendering it a mindless slave to Leon's own body, while still being inextricably fused to his circulatory and nervous systems. It cannot be removed, but it is little more than a mindless lump fused to Leon's spine. Leon instead needs to learn to control the unstable abilities it gives him. He can never be fully human again, but he can get close. Superficially. Buried under his skin will always remain the roots or "buds" that can grow into these terrible weapons.
Luis dedicates most of his life immediately after Valdelobos to studying Leon in an attempt to help him gain full control. They're kept in quarantine together for many months.
So post RE4, killing the plaga in Leon doesn't actually reverse any of the physiological changes it made to him, because it interacted strangely with the cocktail of latent viruses within Leon and resulted in this strange mutable situation. But now he has control of it. He can't get it to disappear completely, some scales and claws/teeth are permanent. But he can make the tail disappear, or he can commit fully to monster mode if he wants. It's not fun. It hurts, his senses get weird, and he's not used to the way that body moves, so I'm not sure he's actually ever gonna transform as fully as he COULD. But we'll see. It's fun to speculate.
There are a few instances later on in 9 where I think he would attempt to partially transform, but he tries to keep it as a last resort for Reasons.
Anyway, I just think he's neat and should be able, with Luis's help, to achieve a significant degree of control.
As a result of this, though, his body at its most human is also a lot more DENSE than it looks. A lot of metaphorical "buds" that can sprout into monstrous parts are just hiding beneath the surface.
Okay, here's a proper reference for (Mutation AU / plagas / infected) Leon S Kennedy, at his most mutated. I am shallow and wanted to keep his face largely recognizable! I'm mostly going with the angle of the carapace mostly forming around the anatomy that gets exposed or injured most- his spine, his dominant arm, etc.
The tail is prehensile, doubling as a weapon AND a grasping limb. Uh. Technically also an ovipositor (wasp stingers are ALSO this), but I'm not sure he knows that. It's fine, Luis can do some examination and deduce as much later. Luis is going to be very enthusiastic and supportive.
Notably, removing Leon's plaga does NOT result in immediate reversion to his original shape. A lot of the carapace sheds like an old scab and regrows smoother and more understated, the extra appendages mostly fall off. The tail goes from a crab-like shell to something more dragonfly adjacent. The claws, fangs, and sensory/perception changes are permanent, but not a lot else.
I MAY give him some voluntary control over the mutation expression, allowing him to regrow some of these parts from a mostly human-passing body. Regardless, he's stuck looking like this for longer than he expected. Days turn into weeks turn into months... Luis looks human, Ashley has always been able to pass as human.... and Leon still has chitin scales, claws, fangs, and a (substantially reduced) tail. He's gonna be wrestling with dysphoria for a while, partly because despite everything... it doesn't feel entirely *wrong*.
Las plagas mood board. 🖤
Attempt at a Plagas Leon design again because I wasn't quite satisfied yet, if you wonder why he lost his shirt it's for design reasons purely
Plagas infected Leon. 😩
POV: Dumbass lost his Plaga medication