Animating

First of all i apologise for the thread (since it’s a question and not a picture or anything relevant), but i didn’t see any sub-forum for question so i’ll just go ahead :

how do people animate such video

and i want to know especialy about the neck thing , like how did they do it? i know (from my experience) that’s not possible to do with HAT tools , or is it?
thanks in advance

That’s done in Source Film Maker for TF2.

thanks

What he means is, this is the gmod section.
You should post this in the TF2 section instead.