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Yes, people who bought on Epic can transfer their key from 8/15/24 - 9/15/24, on this page. If you do the key transfer, and you want the Content Pass, you will need to purchase that off the same page, via Stardock. The Content Pass is not currently available for purchase (for Steam) outside of our website.

I own Sins of a Solar Empire II on Epic, what are my purchase options for getting the Content Pass or Premium Edition?

You can purchase the Premium Edition or the Content Pass via Epic..

Features

Does multiplayer work between Epic and Steam?

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