Dlc · Released

Sins of a Solar Empire II: Harbinger

The long wait is over as the deadly faction, the Eidolon, arrives in Trader space! Command the power of corruption, stealth and psionics to conquer all before you in this major expansion for Sins of a Solar Empire II.

Release date
September 3, 2026
Platforms
Windows
Developer
Ironclad Games Corporation, Stardock Entertainment
Publisher
Stardock Entertainment
Sins of a Solar Empire II: Harbinger artwork
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About Sins of a Solar Empire II: Harbinger

The Vasari have been running for nearly 10,000 years from the 'great threat' that destroyed their empire. For 35 years, they’ve warned anyone who would listen about it drawing near…. Now, they have arrived: the Eidolon. The Eidolon don’t value typical assets like other races, but they do exploit them as a way to spread their corruption more effectively. They seek only to corrupt those they encounter, transforming them into something else to empower themselves. FeaturesPlanetary Transformation: The Eidolon spread corruption across the galaxy to empower themselves and their worlds.

As populations fall under the Eidolon’s influence, their planets gain corruption over time. Once a world has fully fallen, it can be shrouded, greatly expanding the upgrades that planet can support. Unit Corruption: Corruption empowers Eidolon units in combat as well as weakens them. As an Eidolon ship gains corruption, its hull dwindles while its offensive power increases. Enemy forces can become infected by corruption, giving the Eidolon another advantage. Null Weapons: Eidolon weapons are far more advanced than those of the other factions; and can negate shields and spread corruption against enemies.

Cloaked Ships: Subterfuge is one of the great enemy's sharpest weapons, as seen on the Kalizaeth Profaner support capital ship. New cloaking and detection systems let the Eidolon appear and vanish at will, enabling hit-and-run tactics that reward patience and punish anyone caught off guard.…

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Sins of a Solar Empire II: Harbinger artwork
Sins of a Solar Empire II: HarbingerSteam · Dlc · Available
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Sins of a Solar Empire II: Harbinger reviews & player comments

Store ratings and available player reviews. Review snapshots show their last refresh date.

★ 6.1/10Steam · 280 ratings
SteamLast checked November 4, 2026

Most helpful8

Not recommended
The Eidolon are a decent add-on and finally add a completely new race to Sins after like 10+ years. Their music tracks are excellent and…
Recommended
Good new race, with some new fun mechanics to play around with. Corruption, cloaking, "elite" powerful units that outperform other races' but cost much more.…
Recommended
The best designed faction in the game. Corruption is integrated through the economy and fleet. They did great work on the look and feel of…
Recommended
As of this writing, the Harbinger DLC is $34.99 CDN. I got it for considerably less as I got a season pass to all four…
Recommended
I know some folks are angry at the price for a single new faction and some smaller additions. But the Eidolon feel fresh and very…
Recommended
Great faction. It is complicated to understand and master but very rewarding when you do. Thank you for your past work. ;..)
Recommended
What are good/selling points of the DLC? + The expansion adds a whole unqiue race and mechanics to the game. + This includes new "shrouding"…
Recommended
*Received Free due to Season Pass* Greetings! Finally getting around to reviewing Harbinger the long awaited 4th faction for the Sins of a Solar Empire…

Most recent8

Recommended
Despite my negative first impression, Eidolon grew on me as I play with them for some time. At first I thought that corruption mechanics was…
Recommended
As of this writing, the Harbinger DLC is $34.99 CDN. I got it for considerably less as I got a season pass to all four…
Recommended
This is the content injection the game desperately needed. ITS GREAT
Recommended
Good new race, with some new fun mechanics to play around with. Corruption, cloaking, "elite" powerful units that outperform other races' but cost much more.…
Not recommended
You can't even release a tutorial to teach people this new faction. I have had so much fun with Sins 1 and Sins 2, and…
Recommended
The new faction is fun to play and has good theme, fighting against them also feels tough without being impossible, which works for their lore.…
Recommended
The best designed faction in the game. Corruption is integrated through the economy and fleet. They did great work on the look and feel of…

Short excerpts linked to their source. The score above uses aggregate storefront ratings—not these few comments.