You have to loot a lot of things in Pandaria zones. And almost all those things have a low chance of drop. It might take a few months. Like drop chance of Reins of the Thundering Onyx Cloud Serpent from Huolon is 0.9%, and don't forget that Huolon loot can be getting only ones at week. If you don’t want to spend your time killing a lot of mobs, we can help you with it. Our best players will defeat them for you.
Here you can buy Going To Need A Bigger Bag for EU or US Servers.
Also you'll get guide for receiving Going To Need A Bigger Bag