Rainbowlex, it isnt an avatar, thats why

The avatar is missing script so we can't upload it, even with modular avatars

king12, dilroopgill, It works you need MA (Modular avatars) I put it on 5 avatars, it works. Just drop the prefab, align the "muzzle" to the avatar's mouth or whereever you want the fire to come out of and BOOM it works.

Translated From the ReadMe

[Installation]
① After installing ModularAvatar, import the Unitypackage
② Drag and drop the prefab from "prefab_MA" into the avatar
③Adjust the position of “particle” in the prefab to suit your avatar mouth
④Upload the avatar

[How to use]
A "Fire" toggle will be added to the ExpressionMenu. After the "Fire" Toggle is enabled, you need to make a fist gesture with both hands to make the fire come out.

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king12, all you really need is the effect, a way i setup breath is a toggle for it to be activatable, a head contact receiver that takes the input of both my right and left hand to be true, now when you have it toggled and put your hands up to the contact receiver turn on the animation, turn it off when hands away (make it lose velocity and size over 1s to make it smoother if you end it early, prob unnecssary can just give it an exit time for the full length of animation, i just like ending stuff early smoothly)king12, i think this one is straight up just a toggle or button you hold that turns the animation on and off.

prfab no work only has missing scripts