The first DLC expansion for Sins of a Solar Empire: Rebellion, labelled "Forbidden Worlds" is set to release on June 5. The 4X strategy game from Ironclad Games and Stardock Entertainment is once again pushing the boundaries of space supremacy. Additional content includes new planets, technologies, planetary bonuses and everyone's favorite OCD instigator, Steam achievements.

If you have been out of the loop on Sins of a Solar Empire: Rebellion, you can read our co-op review here for a refresher. Essentially, the game is a large scale galactic war between the three factions and the loyalists and rebels within them. Set in deep dark 'Trader Space', the rival races have yet to see their greatest challenge, which becomes apparent in the new expansion. It is up to you to command your fleet and discover new, forbidden, worlds filled with wealth, danger, and mystery.

Here is the official feature list from the Sins of a Solar Empire website:

Four new planet types to colonize and exploit (Barren, Ferrus, Greenhouse, Oceanic), each created with beautiful high-res textures.

New Planet Specialization System: Dedicate your worlds to either social or industrial output. Devoting your planet to social improvements will increase its population and culture, at the cost of trade income and ship production. Choosing an industrial path will limit your growth and culture, but make your planet a trading and ship building powerhouse.

15 new research subjects allow the races to conquer and expand onto the forbidden worlds.

Discover 40 new planet bonuses during your exploration of the galaxy, unlocking the dark past of the Sins’ universe.

Unlock five new Steam Achievements and display your mastery of forbidden space!

There are a couple weeks to prepare for the DLC, so that leaves enough room to finish maybe two Sins games. It will be available for $4.99 directly from the Sins site, Steam, Gamestop, GamersGate, and GameFly. It's time to head back into space and conquer or befriend everything you discover.