It's pretty rare that a game's level editor is released prior to the game itself but Unknown Worlds Entertainment is doing just that with people who pre-ordered their upcoming FPS-RTS game Natural Selection 2. Today the developer released the "pre-alpha" version of the game to those folks which basically amounts to the level editor and some environmental artwork for the game.

This release is mostly for folks who want to tinker with the level editor and start making maps for the game before its release (currently set for sometime in 2010). Unknown Worlds might even use some of the best third-party maps and put them into the final game.