Download Population Engine Free Unity. 

Instantly breathe life into your cities, villages, and dungeons with the ultimate AI crowds and procedural spawning solution for Unity!

It can mass-generate any object – people, buildings, trees, props – and intelligently place them in your scene around obstacles. The AI system instantly drives NPCs into motion with pathfinding and animations – no programming required! Populate your scene in minutes, not weeks or months!

WebGL Demos | 40-Page Manual
Video Tutorials (Watch on this page)

FOR NPCs: Automatically places your characters and vehicles in your scene, around obstacles such as buildings, cars, tables, etc… It then powers your NPCs to move around to simulate a living population. NPCs automatically stop and look at specific objects. You can set up unlimited routes and traffic directions. Includes advanced movement script with Head Look Controller, animations, Mechanim Animation Controller, and free humanoid models for testing.

FOR PROPS & TERRAINS & MORE: Not just for NPCs! You can generate anything you want – trees, props, rocks, cars, etc… Imagine placing 100 rocks in a forest by hand, making sure they don’t overlap any buildings or people. You can also spawn grass/trees on anything, not just terrain. You can even spawn random sounds.

FOR LEVEL DESIGNERS: In-editor tools allow you to manually “paint” objects into your scene with a single click. It automatically detects props, tables, rocks, etc… and places your people around them. All without any coding! Effortlessly insert hundreds of objects into your scene.

FOR DEVELOPERS: Everything here can be done without any coding. If you want more advanced integration, use our simple API. Sample scripts included.

FOR PERFORMANCE: Generate population only when your player moves into that area.