If you’re looking to have your friends join you and play Heroes of the Storm, then this weekend is the best time to do it. Blizzard has announced that they will be unlocking all heroes to all game modes for Heroes of the Storm this weekend starting from January 13 to 10am PST on January 17 (if my conversion is correct) or 2:00 A.M. Wednesday local time.
So get to play with 60 heroes all hailing from the various Blizzard titles now. For more info you can check out their link on the event.