Valve hasn't announced a timetable for the release of the Knux controllers and Episode 3, but they promise that they will make 'a reasonable effort' to release before Half-Life 3's debut.

Any narrative issues should sort themselves out once they've seen the new version of the Barnacle we've been working on since 2008. We believe the VR experience will sufficiently transform how players experience the Half-Life story, even in 15 minute intervals. When asked if the stories of Half-Life 2: Episode 3 and Half-Life 3 would overlap, Gabe Newell said he 'wasn't sure yet.' Using Valve's newly unveiled Knux controllers, the game will allow you to swing a crowbar one to one in the Half-Life world. The new game mechanics, improved game engine and next gen console’s led Valve to creating Half Life 3. Half-Life 2: Episode 3 will be a fifteen minute VR experience that bridges the gap between Half-Life 2 and Half-Life 3. Valve decided to not make a Half Life 2 Episode 3 because the story will vary a little bit from the original, all though it will include many of the main characters. While players still have a bit of a wait for more crowbar action, Valve also has a few more Half-Life treats in store for 2019.

Half-Life 4 will come out on as it seems Valve can count to 3 when it comes to release dates, just not game titles. Discovery can be hard, and Epic will be able to push the Valve name to a whole new audience. Half-Life 4 will not be a VR exclusive like Half-Life: Alyx. We just want to ensure that players have the best experience with our new game. What we can say is that Half-Life 3 will live on the Epic Games storefront for a year after release. Details about our deal with Epic Games are confidential. fans began hoping that a full sequel would eventually appeara Half-Life 3 filled with further gaming revolutions and the kinds of surprises only Valve could dream up.

Half life 3 announcement