Stardock has announced the full release date for Siege of Centauri.

Their sci-fi tower-defense and RTS hybrid will launch for Windows PC (via Steam) on September 12th, hitting its full release.

Lead designer Derek Paxton talked up the game, and how ambitious it is for both a strategy game and a tower defense experience.

“With tens of thousands of enemy machines pouring toward your base, we wanted to give players a very new experience of what it means to defend themselves against overwhelming odds,” Paxton said.

He added, “In addition, we’ve incorporated several strategic elements into the genre, including defending resources and deploying rapid response teams to battle. Our goal was to provide players with difficult choices about which areas to defend and which areas to let go, leading to greater strategic depth.”

Here’s a rundown on the game:

Siege of Centauri puts you in command of the defense of Earth’s first interstellar colony. Thousands of alien machines are descending on the helpless colony and only you, with your arsenal of fast-deployed orbital defense structures (FODS) can stop them.

The enemy comes in all shapes and sizes, challenging you to counter them with the right defense in the right place. Siege of Centauri combines the best elements of classic tower defense games with the strategic depth Stardock has delivered in past titles, including Sins of a Solar Empire: Rebellion and Ashes of the Singularity.

Battle across the surface of an alien world through a series of story-driven campaigns or fight for survival in a doomed region to see how your skills match up against thousands of other players across the world.

Siege of Centauri is now available for Windows PC (via Steam Early Access) for $9.99.