Legend of Korra GTS... Sort of
 

I'm not sort if this counts but thanks to Nick.com, they released the season 2 finale of "The Legend of Korra" and during it there is a GTS Moment in it

So when Korra meditates in this anicent tree that is the gateway between the human and spirit worlds, her inner-spirit grows in a slow process to Monster size to fight this other monster spirit

Yeah, I'm not saying a lot because they are people who haven't it yet so here is a link- http://www.nick.com/videos/clip/lege...-k4y3l2e1.html