Throw a snowball at Muradin Bronzebeard during the Feast of Winter Veil.
IMPORTANT: Achievement can only be earned while Feast of Winter Veil is active.
Snowballs can be obtained from several sources. The best time and location is during Winter Veil at the Ruins of Alterac in Hillsbrad Foothills. There are oodles of http://www.wowdb.com/objects/178609-holiday-snow that contain snowballs. Snowballs are additionally sold by Smokywood Pastures vendors for 10 copper.
This achievement requires the (Alliance) player to travel to Ironforge. Muradin Bronzebeard is located in chamber with others of the Council between The Commons and The Great Forge.