Fixing broken facial expressions on edited avatars
Macaroni Tips
If an edited avatar's eyes, mouth, or default face breaks after applying facial anim clips, re-record the BlendShape values in the Animation tab so the clips match the current face.
Adjust expression clips for the edited face
Most expression issues come from anim clips containing BlendShape values that no longer match the modified avatar. Fix only the keys that are causing the visible break.
Before you start
This is for avatars whose face has already been edited, where the provided facial anim clips no longer match the current face. If basic anim editing is still confusing, read Basic checks when importing anim files into Unity first.
BlendShape sliders live on the Skinned Mesh Renderer. Unity's documentation describes 0 as no influence and 100 as full influence, which is exactly why expression clips can break after face edits: the old numbers are still being animated.
Duplicate the original expression clips before editing if possible
The face mesh may be named Body, Face, Head, or something avatar-specific
Turn Record off after editing so you do not accidentally key unrelated values
1. Add the expression FX to the avatar
Drag the expression FX or anim asset from a path like SexyPose > Anim > XXX_FX onto the avatar in the Hierarchy. Folder and file names vary by product, so use the screenshot as an example.
2. Open DefaultFace
First, get to the baseline expression clip you want to edit. Select the avatar object in the Hierarchy, double-click the anim file in Assets, and open the Animation tab.
In the Animation tab, use the clip dropdown under Preview and choose DefaultFace. Do not press Record yet here. This step is only about making sure DefaultFace is the active clip.
DefaultFace is the baseline the face returns to. If this baseline no longer matches the edited avatar, every expression can look slightly wrong.
3. Select Body or Face and enable Record
After DefaultFace is selected, choose the object that contains the facial BlendShapes. In the screenshot it is Body, but some avatars use Face, Head, Body_001, or another name.
Once the face mesh is selected, press the red Record button in the Animation tab. From here, changed BlendShape values will be recorded as keys into DefaultFace.
You select Body or Face so the BlendShape sliders appear in the Inspector. If the avatar root is selected, the face sliders may not be visible.
4. Enter BlendShape values and record them to DefaultFace
When an edited avatar's expression breaks, the old anim values usually no longer fit the current face. In the Inspector, find the relevant BlendShape and manually type a value that looks right for the edited avatar.
Because Record is on, the value you type becomes a key in DefaultFace. The goal is to save a new baseline face that matches the modified avatar.
Small passes are easier. Adjust the eyes first, then mouth, then brows or cheeks. If you change everything at once, it becomes hard to tell which value caused the problem.
5. Stop Record and check with Preview
After all needed keys are recorded, stop Record first. Then select expression clips one by one from the Animation tab and use Preview to check whether anything still breaks.
If Record stays on while you touch unrelated values, those values may also be recorded into the clip. Turn it off as soon as this pass is done.
6. Adjust broken values while watching Scene view
If you find a broken expression during Preview, slide the vertical line in the Animation timeline and check which BlendShape is active at that moment. Adjust the value while watching the face in Scene view.
In the screenshot, the eyes are the broken part, so the eye-related key such as eye_close is being checked and adjusted. Match the visible issue to the key name: eyes for eye keys, mouth for mouth keys, brows for brow keys.
If one expression still looks off, do not turn Record back on for this pass. Adjust the relevant BlendShape value directly while watching the Scene view. Start by removing the obvious breakage, then fine-tune the small expression differences afterward.
Common pitfalls
You cannot find the BlendShape sliders
You may be selecting the wrong object. Look for the object with a Skinned Mesh Renderer and visible BlendShape sliders.
The value does not stay after editing
Check that the correct avatar is selected in the Hierarchy and that the target clip is selected in the Animation tab.
Another expression breaks after fixing one
Several clips may use the same BlendShape. Preview DefaultFace and the commonly used expression clips together.
