The Greeveling is the Dota 2 (the DotA by Steam) winter holiday special.
It's a whole new map, featuring a small evil-looking creature, who is claimed to have stolen your gifts!
Your mission is to destroy the greevelings and their eggs, specially before they hatch. In a normal 5v5 battle, the first one to slay 10 greevelings wins the battle.
Furthermore, there are special holiday gifts, which have limited durability.
Misery piled on misery! As the cold closed in, how we looked forward to Frostivus. Instead we get The Greeviling! The shops have been plundered, our gifts ripped open, our precious items scattered through the woods by a dire tide of Greevils! What caused this swarming chaos? Who hatched all those Greevil eggs? Who can we blame for burying us in this horde of mischievous imps? What's that you say?
Oh and another thing which is fun to do is to see your favorite characters slice on the ice at the top-mid-bottom line.