UPDATED:
http://hearthstone-videos.com/all-nemsy-necrofizzle-emotes-updated/
IMPORTANT!! READ FIRST: UPDATE-The following process might be more effective-
1)The hero comes out at 17th October, a few days before that, create a fireside gathering using a notable cafe in your area here(make sure to find its latitude, longitude beforehand):
https://us.battle.net/hearthstone/en/fireside-gatherings/create
2)After two or three days, if your application is accepted, when it is time for hosting, use the fake location app to spoof your location at the cafe, use four android devices with spoofs or run Nox android emulator
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwj8h5fLm-bWAhVLv48KHWfVCg0QFggnMAA&url=https%3A%2F%2Fwww.bignox.com%2F&usg=AOvVaw2Q0J9XD04naww4jmZHiFWA
to open four android emulations using nox multidrive from your desktop with four accounts (Each instance of Nox you run must have Hearthstone and Fake Location installed). Devices must be on same wifi. Thats it, some games if required.Go to the Fireside Gathering website and establish the cafe location as a Tavern.
3)Schedule another gathering that runs from before the 17th of October for a few days, play using four accounts with spoofs under the same wifi this time you might get Nemsy Troublefizzle.