The announcement was made on Twitter, via the official Valve account. No other details were in the tweet, beyond a link to the game’s Steam page. There’s nothing that we don’t already know there either.
— Valve (@valvesoftware) February 13, 2020 But to quickly recap, the plot of Half-Life: Alyx sits in between the events of the first and second game. It is a VR-only title, but it is compatible with any VR headset that works with SteamVR. Of course, if you’re one of the lucky ones to own Valve’s own Index VR headset, then you’ll actually be getting the game for free. For those who don’t have it, though, you’ll have to get some other VR headset if you’re interested in Half-Life: Alyx. Even though Valve has previously expanded the availability of its Index VR headset, Malaysia wasn’t one of the countries to get it. And even then, in some of the regions where it is available, it was sold out within a week. (Source: Valve / Twitter)