After some confusion as to whether the storied “A-Life” simulation system was still present in Stalker 2: Heart of Chornobyl, GSC Game World has confirmed that it is—and also that, yes, it’s got some issues, and also yes, they’re working on it.

For those new to the world of Stalker, A-Life is essentially the underlying system of simulations that governs the behaviors and interactions of NPCs and monsters in the game. “The gist of the A-Life is that the characters in the game live their own lives and exist all the time, not only when they are in the player’s field of view,” OG Stalker programmer Dmitriy Iassenev said in a 2008 interview about the original Stalker with AIGameDev (via the Wayback Machine).

A-Life is ambitious, powerful, and—surprise!—janky as hell. It’s also central to the Stalker experience: For as weird and glitchy as they get, the Stalker game worlds feel alive to me in a way that no other game has matched. When something funky happens that obviously wasn’t supposed to happen, it’s often equally clear that it could have happened in the messy stew of the Exclusion Zone, and the fact that it did happen kind of makes sense—and as often as not those unexpected outcomes brought me an odd sort of joy.

There was, and persists, some confusion over whether A-Life had returned in Stalker: Heart of Chornobyl, expressed across numerous posts about it on the Stalker 2 subreddit. The good news is that it’s still there; the less good but entirely unsurprising news is that it needs work.

“There are several known issues with A-life 2.0 system that we are aware of and are working on fixes/improvements,” GSC Game World community manager Mol1t wrote recently on the Stalker Discord. “We know that this system is very important to the Zone having an immersive atmosphere, and we will do our best to fix the known issues.”

GSC Game World repeated that point earlier today in a post on X:

One Reddit post that caused particular consternation noted the removal of a reference to A-Life 2.0 on the Stalker 2 Steam page. GSC Game World didn’t address the removal directly but I think the most likely reason, as numerous redditors pointed out, is simply that Stalker fans know what A-Life is but nobody else does, so having it in there is more likely to cause confusion than do any good.

For me, the presence of A-Life 2.0 in Stalker 2 was immediately confirmed by Joshua Wolens’ tale of a military checkpoint and a pack of feral dogs in his review: Stalker 2’s stars had aligned in such a way that these dogs, on their travels, happened to walk right into the checkpoint I needed to get through. Like a plague sent by God, they devoured every troop in there, taking heavy casualties themselves as the panicked soldiers let rip a hail of gunfire that turned night into day. After 15 seconds my problems were a dim memory. I put down the few remaining pups and carried on.

That, folks, is A-Life in action. It doesn’t get any more Stalker than that.