Hearthstone-styled tankard full of beer with the game's logo centered on it. Since it was obtainable during the 2017 "Oktoberbrawl" event, it's a clear nod to the beer nature of the real life Oktoberfest event. Still, the game takes place in a tavern, which further boosts the connection.
Tweet (quite late) by @PlayHearthstone unveiling the emotes: https://twitter.com/PlayHearthstone/status/913463338306125824
Tweet by @emotetracker: https://twitter.com/emotetracker/status/907337998030733313
Hearthstone event blog: https://hearthstone.blizzard.com/en-us/news/21028613
Oktoberbrawl 2017 emotes: 
Twitch - Global Added Sep 10, 2017 supinic.com
