Café de Nuit

While I am not the author of the original Brutes and Banshees article which expanded the Calibans into subraces and made them fully customization, I am a fan of it and plan to add to it with more customizers, as well as two new subraces: Masterminds and Phantoms.
Masterminds: A rarer breed of the Caliban, they are perhaps the most pitiable of the caliban, being truly disabled by their disfigurement. Defined by overdeveloped heads and underdeveloped bodies, being either thin and lanky like a pumpkin headed scarecrow, others so hunch backed they look like an over-sized fetus. It seems in exchange for their disfigurement, fate has decided to give them reprieve with hyper-developed minds. Even the dullest Mastermind is smarter than the average man, and many exhibit psychic abilities.
Masterminds are found all over the core, as well as isolated domains, though the largest population is found in the southern core, particularly in Barovia. Pure blooded barovians say such beings are the result of Thaani breeding outside their ethnic group, and is used as cause to isolate them. The Thaani pay no mind to these rumors, and regard the Masterminds with some pity. They believe they are the result of the Silent Masters experimenting, like what happened to them so long ago. Considering how some masterminds being to developed other mutations such as extra eyes and even tentacles, there may be truth to this belief. Some Masterminds have also been attributed to incestuous bloodlines, as well as families cursed by pride, or obsession with academia.
Masterminds rarely live long thanks to their twisted bodies and appearance, being seen by their family as burdens and sources of shame. Those who survive often become bitter at the world, and rely on their intelligence to get revenge for their lot. Many turn to crime, planning heists, assassinations, and more. Others are content to live with society at a distance, corresponding with academics and scholars via letters

Phantoms: Perhaps the rarest of breeds, Phantoms live up to their name with a unreal, changing nature. Their physical appearance often changes in subtle ways, with lips and nose and chin subtly changing. Many are marked with eyes either milky white or pitch black, with a grey, ashy skin. While this alone is unnerving, what truly disturbs is a sort of air around them. They seem to exude an aura of unreality, as if the world is unstable around them. Other times, it gives them a sort of natural invisibility, compelling others to not notice them unless they wish it. The shadows around them seem wavy and unnatural. And all are horribly insane.
Phantoms have a natural affinity with magic, specifically illusions.
Phantoms can be found around the Shadow Rift, as well in Western Core in the more advanced domains. While there location of birth could attribute the mutations to Fey meddling, so many times family history show no precedent for such a thing. Shadow Fey show a natural hatred for Phantoms, saying they are "touched by the Twilight" and fear they will cause ruin for all Arak.
Some in the Fraternity of Shadows theorize that Phantoms are the result of contamination by the Plane of Shadows into the land of mists, with some fearing it will contaminate their own bloodlines. As such, family men amoungst the Fraternity have begun to search their own children for the telltale signs.

Ideas for additional Caliban mutations: Withered Limb, Vestigial Tentacle, Milky Eye, Leech Lips, Snake Fingers, Bulbous Head,
Dead Presence, Newt's Limb, Ashen
Still not familiar enough on 3e to write specific rules, but here's sorta what these are supposed to do

• Withered Limb: One of you arms is withered and lame, whilst the other is robust, as it if has stolen the vigor of the other. The withered arm is less effective while the robust limb more effective. Overall weight capacity and two-handed weapons unaffected (potentially)
• Vestigial Tentacle: A small, almost tail like grown upon some random location of the body. Hearkening back to whatever bygone era of humanity which may have needed such a growth, it trembles with ancient instinct of danger. Gives a bonus when it comes to sensing danger
• Milky Eye: You eyes are white and cloudy, much like an aged raunie's. Gives one the ability to see through certain illusions, at a cost of your normal sight being worse (a penalty to hit, or something. Again, still thinking up rules)
• Leech Lips: You mouth is distorted into a permanent hole, with swollen lips forming into an unbroken ring, and needle like teeth. Can while grappling an opponent choose to leech off of a portion of exposed skin, doing 1 temporary con damage and gain 1d6 health. For your inhuman appearance you have a -1 charisma penalty
• Snake Fingers: You fingers are long and thin, comparable to twigs. Gain +2 to sleight of hand checks
• Bulbous Head: Your head is swollen in size, often misshapen. Your mind is as developed as your cranium and so you gain +1 intelligence, but must have custom made helmets/hats.
• Dead Presence: You seem to give off no real presence, your breathing is near silent. Being as close to invisible as possible, you gain a +2 to stealth, but -2 to intimidate
• Newt's Limb: One of your limbs is particularly deformed, either greenish and slimy, or elongated, or covered with scales. This limb can regenerate naturally, even fully regrow itself if severed over a course of 1d4 weeks. However, this limb is also very weak and more easily harmed.
• Ashen: Your skin is dark-grey to black in complexion, so much so you seem to absorb light. You gain resistance to radiant damage

That's what I have so far, admittedly not much. I would appreciate any thoughts on the mutations, how I could make rules for them or fix those that feel unbalanced.