Rigging help

I’ve got a model of Ness from Smash Bros Melee and I need to rig him, is there an easy way to do this inside of unity? Whenever I try it asks for body parts X isnt a parent of Y and say there would be a body part linked to the opposite side e.g arms would be the same in polygon group.

Hey, take a look at the docs for rigging models: Unity - Manual: Rig tab

and docs for preparing your model: http://docs.unity3d.com/Manual/Preparingacharacterfromscratch.html

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