There’s a strange, hard-to-define appeal to trudging about an eastern european irradiated hellscape, gun in hand, dodging bullets while trying not to stumble into some barely-visible hole in reality that’ll turn you inside out. Strange, but it’s what has held the STALKER series and its fans together all this time.

Vostok Games, a studio founded by ex-STALKER developers, have spent the past few years hard at work on Survarium, a free-to-play multiplayer take on the concept. Entirely PvP focused until now. The latest update to the game has added a lengthy co-op mission, hopefully the first of many.

Still lost in the Zone? Check out our roundup of essential mods & fan-games for aspiring STALKERs.

The appeal of the Stalker series has traditionally rested on their sandbox-focused structure and open world, meaning that the arena-focused, previously PvP-only Survarium has had an uphill struggle gaining traction with series fans. Still, Vostok Games have kept on at it, and this large update feels like a significant milestone.

Pitting the players primarily against waves of NPC soldiers and the occcasional traversal challenge laden with damaging anomalies, the mission itself seems lengthy, taking a decent squad well upwards of an hour to complete, albeit broken up into several smaller sections.

It’s still early days yet for Survarium (hence the Version 0.50 label), but this mission offers a solid, co-op approximation of the classic series’ best moments, with enough freedom and enough unpredictability in the AI to lend it some replay value. Here’s hoping they continue to build on this foundation for many years to come.

Plans are for the game to eventually support free-roaming PvE adventuring in the style of the classic STALKER series, presumably with a few non-human enemies as well, but for now this mission will have to suffice for those eager to shoot something other than rival players.

Survarium is available via Steam Early Access. It’s free to play, but there are a variety of gear bundles you can purchase at present.