Andrii Levkovskyi Director of AI

What are the key differences between STALKER ’s A-Life 1.0 and STALKER 2 ’s A-Life 2.0?

A-Life 1.0 was designed for relatively small, location-based worlds, not a true open world, and using it like in the first STALKER would have been impossible for numerous reasons, including performance, for example. The big open-world map without the loading screens is a dealbreaker here. We needed a new system to bring the Zone to life around the player.

What are the specific open-world challenges?

While UE5 is powerful, [the scale of the open world] created immense technical demands and required more computational and memory resources to achieve decent performance across target platforms. We had to shrink the area around the player in which A-Life 2.0 operates in its full simulation. This meant NPCs outside the player’s immediate visualisation range entered a simplified ‘virtual’ mode, only spawning when the player approached. To manage NPC encounters and create a living Zone experience, we [also] introduced the A-Life Director, which acts as a scenario generator, simulating potential clashes from nearby lairs and spawning characters at the edge of the player’s visualisation range. While it enhances players’ experience by providing engaging scenarios, it’s a directed approach, not the pure emergent simulation we ultimately strive for. It was a forced solution to balance the challenges of scale and performance. We acknowledge the community’s frustration over a perceived lack of transparency regarding its initial state [at launch].