Civilization 6 admittedly has alien units, but players still can't get enough. The Ethereal Invasion mod makes it possible for UFOs and extraterrestrial enemies to annihilate our civilization.
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Source: https://steamcommunity.com
If you want to have XCOM and Civilization 6 in one, then you'll be interested in a pair of mods, Ethereal Invasion and Area 51. They introduce UFOs and aliens into the game, in short, everything that tinfoil caps are supposed to protect us from.
The mod's page on Steam Workshop reads that the creator, Alterd-Rushnano, was inspired by the Civilization 5 DLC The Brave New World, which featured XCOM units. In response to dreams of an alien invasion of our civilization, the mod Ethereal Invasion was created.
What's more, the project is compatible with Area 51 - World Wonder Alien Units, so if you want to introduce alien troops into your game and, as the title suggests, Area 51 (as a wonder on the map), it's worth getting in first.
For the modifications to work properly, you must have the Gathering Storm and Rise and Fall DLCs.
The modification itself does not introduce much compared with Area 51. However, as we learn from its description, the consequences of these changes are likely to be dire for humanity.
You can read the full description of the mod on the aforementioned page on Steam Workshop. However, it is worth noting that Ethereal Invasion is being refined all the time. The developer's goal is to "port" XCOM to Civilization , so we can expect many more updates to the mod.
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