First off, I'd like to clarify why this is a triple recipe instead of three separate threads.
As much as I love & support the trio from Kingdom Hearts, I have to admit that Naminé and Xion look a lot like Kairi.
Due to the simplicity of chao, it's very simple (& makes for a clean thread) to make all three by simply using different colored chao.
With that out of the way, onto the recipe!
First, we need a cute little heart of light.
However, it's not that simple.
You have a choice to make!
Will you be making a Kairi, Naminé, or Xion chao?
Here's my personal picks for each character, however feel free to branch out!
(I personally wish there was a darker brown chao to make KH3 Xion!)
Kairi - Red Monotone, Red Two-Tone, Red Shiny Monotone, Red Shiny Two-Tone*, Garnet^, Pink Monotone, Pink Shiny Monotone, Ruby^
Naminé - Yellow Monotone, Yellow Shiny Monotone, Brown Shiny Monotone, Gold^
Xion - Black Monotone, Black Two-Tone, Onyx^
*This color requires a modded fix to appear as shown in this guide
^Jewel chao may or may not be available without hacking depending on your version of the game
For the rest of this guide, I will be going with a Red Shiny Two-Tone for a Kairi chao.
Regardless of what seems to be aimed specifically at Kairi in this guide, please use these steps for all three characters!
As Kairi has a heart of pure light, we need to reflect this in the chao!
By using a Hero character (Sonic, Tails, or Knuckles) or Hero Fruit, shift the chao's alignment towards the hero side!
Kairi isn't native to Destiny Islands, so she'll need to learn how to swim!
Make sure to give her plenty of Yellow Chaos Drives or animals that boost the swim stat!
Looks like she's doing pretty good!
Throughout the surprisingly short time frame within the series, she and her friends have matured quite a bit.
Go ahead and let this chao evolve! Don't worry, they'll still be the same chao at heart.
Look at this adorable little chao!
She should be Hero/Swim.
Now onto the second evolution!
This one is more gradual, but I believe can be sped up the more you feed them (Correct me if I'm wrong!).
In order to make those little antennae look more like hair, we'll have to increase her Swim and Run stats.
You can use Yellow and Green Chaos Drives!
If you'd like shorter "hair" than what's shown, try to lessen one or the other. It will, however, not lay as flat.
Finally, you can choose to add any animal parts you see fit!
Given all three characters are humans (I think?), there's really no wrong choices here.
It's all up to personal interpretation!
I personally like condor wings & tails on Kairi and Xion, while opting for pheonix wings & tail on Namine.
Here's a quick summary:
Hero/Swim/Swim-Run, in your choice of color!
Here's a little bonus: They also look cute as Angel/Hero Chaos Chao!
While they have the correct eye color & are immortal, they unfortunately aren't as expressive or customizable.
Now go ahead and train your Kairi, Naminé, or Xion chao to win against any foe that dares challenge them - you know you want to.