The International Dota 2 Championships are taking place now; and what better time to announce something completely unrelated. Valve released a video teasing Artifact, an online card game set in the Dota 2 universe.
There’s practically no information available for the game, although it should be positioned as a competitor to Hearthstone. A vague description of Artifact indicates that it has some sort of Barracks building and summoning minions. Lanes are supposedly also involved somehow.
It’s difficult to say what the game will turn out like. It could potentially end up looking like a more traditional card game; something like what Hearthstone has been doing. That said, the idea of lanes might also present the idea that it could be borrowing ideas from the surprisingly good Plants vs Zombies Heroes.