NPC Metadata
NPC instances edited in Eddy have properties that apply only within a single level. Properties shared by every instance of a particular NPC are instead stored in a separate metadata file (.feznpc.json), avoiding duplication across levels.
Mu is a small, specialized editor for modifying an NPC's shared behavior properties:

NPC metadata is usually stored beside the character's animations:
Character Animations/<Character Name>/Metadata.feznpc.json
Metadata does not store NPC positions, dialogue, or actions. Its properties override the corresponding properties of NPC instances within levels.
Properties
You can edit the following properties:
- Walk Speed: Controls how quickly the NPC moves while walking.
- Avoids Gomez: Makes the NPC attempt to move away when Gomez gets too close.
- Sound Path: Defines a shared NPC sound relative to the
Sounds/directory. For example:
This example uses this line:
Dot/Talk
- Sound Actions: Lists the actions, such as
WalkorTalk, that use Sound Path. An action-specific sound overrides the shared sound.
Reference
A more detailed description of the properties is available in the FEZNPC format reference.