Rigging "Sticky Verticies"

Hi, I’ve been trying to rig this character. After I set the armature modifier to the model and try to move the left arm, it also moves a bunch of verticies from the right arm. At first I thought this might have something to do with the mirror modifier but I applied that and no changes followed.

Here’s the .blend file which should help: Big Scary Monster.blend (778 KB)

In advance, thanks for your help. :slight_smile:

Apply the mirror modifier first, then parent the rig with automatic weights, and it works fine. Well, fine enough. You’ll have to redo the weights around the mouth by hand, but you probably already knew that.