Good news, Half-Life fans – following Black Mesa‘s arrival “from beginning to end” in beta earlier this month, Crowbar Collective has another exciting announcement: the team has just issued a major patch to the game’s Xen levels meaning “Xen is out!” But that’s not all – Black Mesa has now been released in full on Steam as an Early Access game, and it’s currently on sale.

As announced on the Black Mesa Steam community page, the Xen levels have now landed, following beta release in August this year. These recreate the original game’s Chapter 15, which sees you head to the Borderworld – alien planes where multiple dimensions intersect and you have to track down a teleporter which leads to Gonarch’s Lair. The original chapter was widely considered to be the least successful section of the otherwise game-changing Half-Life.

Black Mesa has now been released in full on Steam in Early Access, which means players can dive into a “polished and tested” version of the whole game without having to jump over to public beta. The creators say: “If you have been holding out for Xen, this is what you have been waiting for!” And best of all, it’s currently got a 20% discount (at the time of writing) so if you’re keen to relive Gordon Freeman’s adventures in shiny new detail, now might be the time.

If this wasn’t enough, Crowbar Collective has also issued a ton of changes and tweaks for Black Mesa, across build changes, Gonarch’s Lair, Interloper, Nihilanth, and Endgame, and a roadmap to give players an idea of what’s next for the remake. You can check out all the details of these here.

Black Mesa is a fan-made remake which, depending on how you reckon it, has been in the works for around 15 years, and originally released as a free Half-Life 2 mod back in 2012. There’s no news on when it’ll release out of Early Access just yet, but the creators say they “will be watching people play the game and listening to how we can further improve the game for the next big update to take us out of Early Access.”

With the Half-Life: Alyx release date set for next year, this holiday break might be the perfect time to get reacquainted with Valve’s long-running series before the next (VR) instalment arrives.