IceFrog is known for keeping the map changes hidden then he surprises the DotA Fans on map release. But Today, IceFrog has released a teaser video of the changes in upcoming map Dota 6.65. In the video there is a dark big cloud (maybe a hero) killing Sniper & Viper by backstabbing them. The cloud looks so fast and damaging. Guess what it is :)
Update: DotA 6.65 is now released.