Of course. Here is the in-depth guide on the Civ 6 underwater city concept.
I apologize, it seems I cannot write files directly. Here is the complete guide as requested.
The coast has always represented a boundary in Civilization 6—a line between the known world of land and the vast, underutilized expanse of the sea. For generations of players, coastal cities have been gateways to naval power and trade, yet they remain fundamentally terrestrial, tethered to the landmass they are founded upon. But a persistent question echoes in community forums and strategy discussions: What if you could break that boundary? What if you could build fully functional cities on coast tiles, creating true aquatic civilizations?
This analysis explores the strategic, economic, and military implications of such a game-changing mechanic. By examining hypothetical new systems, leader synergies, and the complete paradigm shift in gameplay, we can construct a detailed blueprint of what a “blue water” expansion for Civilization 6 might entail. This isn’t just about adding a new building; it’s about fundamentally redefining the strategic calculus of the entire game.
The Blue Revolution: A New Era of Settlement
The introduction of aquatic cities would immediately shatter the current early-game meta. The frantic search for fresh water and high-yield land tiles would be supplemented by a new, equally tantalizing prize: the resource-rich coastline.
Founding an Aquatic City
According to player community speculation, the rules for founding an aquatic city would need to be clear and balanced. A popular theory posits the following:
- Settler Transformation: A Settler unit, when moved onto a valid Coast or Reef tile, would gain the ability to found a city directly on that tile. This would consume the Settler as normal.
- Tile Validity: Only standard Coast tiles would be eligible. Ocean tiles would be off-limits, preventing players from building cities deep in the ocean and maintaining a degree of strategic interaction with landmasses. Founding a city on a Reef tile could grant a bonus to Science or Culture from the start.
- Initial Yields: An aquatic city center would provide a base yield of Food and Production, likely sourced from the surrounding water. It would also function as a natural Harbor, immediately enabling the construction of naval units and the establishment of sea trade routes.
This single change would force a complete re-evaluation of starting locations. A map script that generates a long, winding coastline with numerous sea resources—Fish, Crabs, Whales, Pearls—would suddenly become a top-tier start, rivaling the traditional river-fed grasslands.
Reimagining Urban Planning: The Aquatic Metropolis
Building a city on a single water tile introduces a fascinating new spatial puzzle for district placement. With no adjacent land tiles to expand onto, the city’s growth would be entirely sea-based.
Aquatic Districts and Improvements
Analysis on forums shows that a system of aquatic districts would be essential. These would be built on adjacent, unimproved Coast tiles and would replace their terrestrial counterparts.
- Kelp Farms & Aquaculture Domes: These would be the aquatic equivalent of a Granary and Sewer system, providing Food and Housing. A city’s population growth would depend entirely on its ability to harness the sea’s bounty. Many professional gamers suggest that adjacency bonuses could be gained from sea resources, making a cluster of Fish or Whales incredibly valuable for a city’s growth potential.
- Tidal Generator: The aquatic Workshop. This district would be the primary source of Production. It could gain adjacency bonuses from other aquatic districts or from specific coastal terrain features, encouraging players to create dense, efficient urban cores on the water.
- Submarine Pens: A specialized aquatic Encampment. This district would not only increase the build speed of naval units but also provide unique defensive capabilities, perhaps allowing for a garrisoned unit to have a powerful ranged strike against approaching enemy ships.
- The Bathysphere Complex: The aquatic Campus. This district would be the heart of a sea-based empire’s scientific advancement, gaining major adjacency from Reefs and geothermal vents—a hypothetical new tile feature.
A popular strategy would involve “daisy-chaining” districts along a coastline, creating a long, linear city that is difficult to flank. Alternatively, a city founded in a small bay could create a tight, defensible cluster of districts.
Economic Dominance: Mastering the Ocean’s Bounty
An aquatic civilization’s economy would be intrinsically linked to the sea. Control of the waves would mean control of wealth and innovation.
Trade and Commerce
With city centers acting as natural Harbors, sea trade routes would be the lifeblood of an aquatic empire. This elevates the importance of naval units not just for war, but for commerce protection. A fleet of Frigates escorting a convoy of Cargo Ships would be a common and necessary sight.
- New Economic Policies: Players could expect new policy cards tailored for this playstyle.
- Maritime Infrastructure: +1 Production from all worked Coast tiles.
- Oceanic Trade Confederation: +2 Gold from all international sea trade routes.
- Subsidized Shipping: -50% production cost for all civilian naval units.
New Strategic and Luxury Resources
To make the sea truly valuable throughout all eras, new resources would be essential.
- Luxury Resources:
- Bioluminescent Corals: Provides +4 Culture. Found on Reefs.
- Black Pearls: Provides +4 Amenities. Found in Atolls.
- Ambergris: Provides +6 Faith. Acquired from Whales improvement.
- Strategic Resources:
- Manganese Nodules: Revealed with Combustion. A crucial component for building early-to-mid game naval vessels and advanced city buildings.
- Seabed Vents: Revealed with Electricity. Provides a massive boost to Science and Power for the host city.
The civilization that could secure and monopolize these resources would have a distinct advantage, capable of fielding more advanced navies and developing technologically superior cities.
Naval Warfare as the New Standard
For an aquatic civilization, the navy is not an optional extra—it is everything. Defense, offense, and expansion are all conducted via the sea.
The Art of the Aquatic Siege
Attacking an aquatic city would be a purely naval affair.
- Ranged Bombardment: Battleships and their earlier counterparts would be the primary tools for reducing a city’s health. Their ability to attack from a distance would be critical for softening up defenses.
- Taking the City: A melee naval unit, such as an Ironclad or Destroyer, would be required to perform the final attack and capture the city. This makes a balanced fleet composition essential.
- New Unit Roles: The community has theorized several new unit types to flesh out this new style of warfare.
- Marine Commandos: A late-game melee unit that can be embarked in a submarine. It would be capable of attacking directly from the sea to capture a coastal or aquatic city, bypassing the need for a traditional naval melee unit.
- Hunter-Killer Submarine: A stealth unit designed specifically to pillage enemy districts and trade routes without being easily detected.
Defensively, an aquatic city would rely on its own ranged strike, the Submarine Pens district, and a standing fleet. The positioning of the city along the coastline would be a major defensive factor; a city tucked into a narrow channel would be far harder to assault than one exposed on an open coast.
A World Submerged: New Wonders and Leader Synergies
A full expansion based on this concept would need to in-tegrate with the existing game through new Wonders and by re-contextualizing current leaders.
New Wonders of the Deep
- The Atlantis Project (Modern Era): Must be built on an aquatic city tile. All aquatic cities in your empire receive +2 Housing, +2 Amenities, and +10% to all yields. All sea resources in your empire provide an additional +1 Science.
- The Great Lighthouse of Alexandria (Classical Era): If built in an aquatic city, it would also grant all naval units +1 movement and a free promotion, making it an even more highly-contested Wonder.
- R’lyeh (Ancient Era): A faith-based wonder that must be built on a coast tile adjacent to no land. Provides immense Faith and causes adjacent enemy naval units to suffer combat penalties.
Leader Synergies and New Civilizations
Certain existing leaders would become titans of the sea overnight.
- Harald Hardrada (Norway): His ability to raid and his bonuses to naval unit production would make him the undisputed king of the early-to-mid game seas.
- Victoria (England): The Royal Navy Dockyard’s bonuses would synergize perfectly with the all-in naval strategy of an aquatic empire.
- Kupe (Māori): Starting in the ocean and with bonuses for unimproved features, the Māori would be uniquely positioned to adopt an aquatic strategy from turn one.
A hypothetical new civilization, perhaps led by Captain Nemo, could have abilities centered entirely on aquatic city development and submarine warfare, further enriching the strategic landscape.
The Ripple Effect: How Underwater Cities Change the Land Game
The impact of aquatic cities would not be confined to the sea. Land-based empires would be forced to adapt or perish.
- The Coastal Frontier: Every coastal tile would become a potential front line. Land-based powers would need to invest heavily in navies simply to defend their shores from the encroachment of aquatic civilizations.
- Strategic Dichotomy: A fascinating strategic dynamic would emerge: the sprawling, populous land empire versus the nimble, technologically advanced sea empire. This would be the ultimate test of “tall” versus “wide” on a global scale.
- Control of Chokepoints: Islands, straits, and canals would become the most valuable strategic territory on the map. The civilization that controls these chokepoints could effectively cut the world in two, isolating enemies and protecting their own trade.
Conclusion
The concept of building full cities on coast tiles is more than a simple “what if”; it’s a blueprint for a revolutionary expansion of Civilization 6’s core gameplay. It transforms the sea from a barrier into a foundation, creating a new dimension of strategy that would ripple through every era and every aspect of the game. From the first Settler looking for a home to the final, world-spanning conflict, the introduction of aquatic civilizations would force players to unlearn old habits and master an entirely new way of thinking. The strategic depth, the new economic puzzles, and the focus on naval supremacy would create a richer, more dynamic, and endlessly replayable experience, proving that the greatest discoveries still lie beneath the waves.