Despite the fact that it doesn't get a ton of updates these days, I still play Heroes of the Storm, and will likely play more once Deathwing (basically, a boss character in a MOBA) hits. But thanks to a presumed BlizzCon promotion, a lot of lapsed players are probably going to want to dive back in.
After getting the tip from a fellow player, I logged into Heroes today to find that every single hero (character) in the game was free-to-play. Like, all of them, even Qhira, the most recent addition. Coincidence? I think not! Today is BlizzCon after all, and the Heroes team is likely going to take the stage to present Deathwing to the world as well as some sort of event, as is customary for the opening ceremony. Don't get too excited though: every character has the "free this week" heroes icon symbol next to it, noting that this likely isn't permanent (a month and change is a safe bet).
Is this a sign of things to come for BlizzCon? Possibly. Heroesis in a position where it needs to really sell itself more to stand out compared to other, more marquee games. But Blizzard really needs to wow the crowd given their current standing, so hopefully this isn't an isolated incident.