If you are looking for the latest official version, it is sold on the Unity Asset Store for approximately . Publisher : Plugin Master

: In older versions like 3.1.1, the toolbar often opened in a separate window. Modern updates (4.x) support Unity Overlays , allowing the tools to sit directly inside the Scene view. Purchasing and Official Sources

Prefab World Builder was created to solve the "tedious clicking" problem in game development. Instead of manually dragging every tree, rock, or fence post into a scene, this tool allows developers to "paint" their worlds with physical accuracy and variety. Key Evolution from 3.x to 4.x

: Version 3.1.1 laid the groundwork, but the latest versions have been optimized for Unity 6 and resolved lag issues when handling dense vegetation or large scenes.

: Uses Bézier paths to instantly place fences or walls along a curve.

: Comprehensive video guides can be found on YouTube for users who obtained the asset via bundles like Humble Bundle.

: Uses physics to drop objects naturally (e.g., scattering rocks on a hillside).

: A detailed guide is available on the Plugin Master website.