Face genes

A chao's face is three inherited genes: a mouth, an eye shape and an eye colour. Six mouths, two shapes and eight colours give96 faces, and a child's is drawn from its parents'.

Front-view stills of one neutral chao across the face-gene space, plus one dark chao showing the alignment override. The eye SHAPE gene shows or hides a separate lid plate; the MOUTH gene swaps the front decal's texture and hides the rig's back mouth layer for every gene but the grin; the eye COLOUR is repainted into the texture rather than tinted over it. The eye frame (al_eye01) is a plain disc with NO PUPIL, so the whole coloured area is the iris, which is the SA2 asset and not a rendering fault. Alignment overrides the eye genes: a dark chao is lidded and tilted, and both hero and dark invert the eye so the gene colour becomes the sclera and the iris goes white.

Mouths and eye shapes

Each mouth is shown twice: wide open on the left of each pair, half-lidded on the right. The lid is a separate plate the renderer shows or hides, and it is what gives a chao a sullen look rather than a bright one.

Toothy grin
Wide open
Toothy grin
Half-lidded
Small smile
Wide open
Small smile
Half-lidded
Big smile
Wide open
Big smile
Half-lidded
Neutral line
Wide open
Neutral line
Half-lidded
Soft curve
Wide open
Soft curve
Half-lidded
Worried wavy
Wide open
Worried wavy
Half-lidded

Where these names come from

The labels above describe what each texture actually draws. The game's own source names one of them differently, and where the two disagree both are listed here rather than silently picking one.

Gene	Texture	Shown as	Named in the game
0	`al_mouth03`	Toothy grin	grin
1	`al_mouth05`	Small smile	small smile
2	`al_mouth07`	Big smile	big smile
3	`al_mouth10`	Neutral line	neutral line
4	`al_mouth11`	Soft curve	gentle smile
5	`al_mouth12`	Worried wavy	worried wavy

Eye colours

The colour is multiplied onto the eye decal, so it tints the iris and leaves the surrounding white alone.

Black
Brown
Green
Blue
Red
Purple
Magenta
Amber

Alignment overrides the genes

A chao's alignment does not just repaint it. Hero and dark both invert the eye, so the colour gene becomes the sclera and the iris turns white, and a dark chao's lids are additionally tilted18° inward. That tilt is the difference between lookingmean and merely looking sleepy: the half-lidded gene lowers the lids level, while the dark override angles them.

Dark alignment override, lidded and slanted 18°
Overridden by alignment

Alignment	Sclera	Iris	Lid	Tilt
Neutral	Takes the eye-colour gene unchanged.
Hero	The eye-colour gene	White	Wide open
Dark	The eye-colour gene	White	Lowered	18°

Rendered from the neutral_normal pack using the game's own face textures and material pipeline.