Galactic Civilizations 3 DLC guide

Galactic Civilizations is a pretty iconic series of sci-fi 4X games that can be succinctly summarised as "Civilization in space". Developed and published by Stardock, it's never really had the same mass appeal as Firaxis' staple turn-based strategy games, but they're still pretty good for what they and offer an excellent interstellar romp.
Galactic Civilizations III was released in 2015 - a year before Civilization VI -although it had been in a state of kind-of early access as early as 2014. In the years since its full release it's been supported by plenty of expansions and smaller DLC packs. The bigger ones offer the most in terms of new content, but some of the smaller ones are worth looking into.
As we've done for other strategy games, we've put some time into sorting through all of the available expansion options so you know what's worth buying, and what's not. We've not bothered to include the two tie-in Star Control: Origins expansions, but commentary on everything else released for the game to date can be found below.
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