Stalker 2 Fixes A-Life and Adds Massive Mod Tools in Patch 1.5

Stalker 2: Heart of Chornobyl just got its biggest patch since launch—and it finally fixes one of the most broken parts of the game. A-Life, the system that simulates NPC behavior in the world, is now fully functional. That means your time in the Zone should start feeling a lot more like the classic Stalker experience players were hoping for. NPCs now act more like independent agents instead of just standing around waiting for you to trigger them.

For those unfamiliar, A-Life is what makes the world of Stalker feel alive. It controls how stalkers, bandits, and mutants roam the Zone, fight, scavenge, and sometimes even die without the player being there to see it. In theory, it’s what separates Stalker from just another open-world shooter. But at launch, that system was barely working. Due to performance issues, GSC Game World had to shrink the radius where A-Life actually functioned. That killed immersion fast.

Now, that problem is finally behind us—at least according to the patch notes for update 1.5, which dropped this week. NPCs can now move, rest, and interact anywhere in the Zone, whether you’re there or not. And if you bump into the same stalker later, they’ll be in a new location, possibly mid-task, or maybe already dead. That small change opens the door for a lot more unpredictability in the way the world unfolds.

“NPCs will continue to live their lives and pursue their goals in the Zone until they meet their end.”

That’s the promise GSC is making with the new version of A-Life, and it’s a major step forward for a game that launched in a rough state.

But this update isn’t just about making stalkers less brain-dead. Patch 1.5, also called the Guns & Looting update, brings a handful of new gameplay features. There’s a new anomaly type out in the wild called the Water Electric Tornado, which sounds as dangerous as it does absurd. You can now also hunt down two new weapons: the Kora handgun and the classic Three-Line Rifle.

AI in general is getting smarter. Combat behavior has been tuned to be less predictable, and enemy reactions have been adjusted across multiple encounter types. Combined with the A-Life fixes, the idea is to make the Zone feel a little more unstable, and a little less like a shooting gallery. Balance changes and bug fixes round it out, targeting both gameplay flow and the survival loop.

Then there’s the modding side. Stalker 2 is now officially supporting mods—but not in a lightweight way. The official modding toolkit is available now through the Epic Games Store, and it weighs in at around 700GB. That’s not a typo. It’s a full dev-level toolset, and you’ll need an empty hard drive to handle it. That size might sound ridiculous, but it shows that GSC is taking custom content seriously. For a series that built much of its legacy on modded builds of the original games, it’s a good sign.

This all comes after a launch period filled with mixed reactions. GSC has been through a difficult development, including delays and production challenges due to the war in Ukraine. Stalker 2 finally arrived, but it launched with bugs, jank, and undercooked systems that held it back. Eurogamer gave it three stars, calling it a “mess of bugs and jank that nonetheless stays faithful to the open world survival shooter of yesteryear.”

Still, for fans of the original games, the potential was always there. Now, with the A-Life fixes in place and modding support officially rolling, Stalker 2 might finally be turning a corner. The mood, the music, the crumbling buildings, and radioactive death traps—all of it hits harder when the people inside that world feel like they’re struggling to survive just as much as you are.

Patch 1.5 doesn’t promise to fix everything wrong with the game, but it does aim to get the foundation right. If GSC can keep this momentum going, there’s still a real chance for Stalker 2 to become the immersive survival game players have been waiting years for.