Civilization 7 has only three ages, but latest clues indicate that devs have already taken care of the option to add more
It looks like the developers of Sid Meier's Civilization 7 have prepared the game for the addition of more ages even before the official release.

Sid Meier's Civilization 7 now has a built-in feature to add additional ages to the game.
We have long been aware that the campaigns in Civilization 7 will conclude before modern times arrive. The developers have even confirmed that the fourth age will be added to the game, but at a later date.
Ages modules and bonuses
If someone doesn't trust Firaxis Games studio, then - as noted by YouTuber GamerZakh - an early version of Civ 7 confirms the modern age because of a bug. When you access the "additional content" section from the main menu and then select "mods," you'll first encounter information about a "module" that introduces the ancient era.
Antiquity is one of the ages that will be accessible right away (alongside the Middle Ages and modern times), which makes this message seem curious. Nevertheless, this appears to confirm that the game enables the expansion of gameplay with extra ages through the use of such "modules."
This is indicated by the fact that the victory conditions menu includes "bonuses" for completing four Legacy Paths in modern times, even though the campaign concludes after this achievement in the current version of Civilization 7.
Of course, there is also the option that the game simply copies part of the interface from previous ages, including the mention of Legacy Points for the next era. Nonetheless, the information about unlocking various bonuses doesn't seem to be an oversight, especially since the interface was supposed to have been improved multiple times with pre-release patches.
Prehistory and release time
As we have already mentioned, the fourth, modern era has already been confirmed. After all, what kind of Civilization ends in the 1960s?
What intrigued the fans more, however, is that the implementation of the entire "modules" of ages could expand Civilization 7 with more than just modern times. How this might work within the new civilization system (altered in each era) is uncertain, but some players are hoping for the inclusion of the prehistoric period.
Nonetheless, even modern times are unlikely to appear in the game too early. First, we are already aware of the development plans for the seventh Civ up to September 2025, and they don't include any mention of new ages. Second, judging by the reviews in the coming months, the Firaxis Games team will be too busy improving their game to think about such serious changes.
By the way, the developers provided the exact release times for Sid Meier's Civilization VII. The game will be available from 9:00 p.m. PT on February 10th for all players and on February 6th for those with paid early access.
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