The team at Twitch are hosting their annual TwitchCon event in Long Beach this weekend, and to generate hype they cut a deal with Hitbox Team (Dustforce, Spire) to build a multiplayer game that's played entirely within the Twitch client.
It's a prominent, interesting example of what a game dev can do with the Extensions toolset Twitch introduced last month, which allows streamers to embed interactive elements (like a dynamic stat-tracking overlay or a live polling system) into their broadcasts.
In this case, Twitch and Hitbox seem focused on keeping viewers engaged by giving them a small multiplayer game to play as various talks and panels are broadcast live from TwitchCon throughout the weekend.
The game, Galactic Disagreements (aka GalDis), assigns players to two teams at random and then asks them to overpower the opposing team by acquiring resources and launching ships. Matches are designed to last about 5 minutes, on average, and the game is currently only playable by viewers using the Twitch desktop app.