forum.freeciv.org

Had this idea since a long time. Could this combination of rules etc. make a conquest of such a city impossible?
(using freeciv-2.6.6, ruleset = default [classic])
Configuration values at game start:
mapgen = default (random)
unitstring = 'cwkxx' (contains a leader unit which is 100%-immune to spy attacks)
frequency of disasters = 0 (none)
gold = 50000 (max.)
global warming = disabled
nuclear winter = disabled
citymindist = 5 (so city squares never overlap)
killstack = enabled
unreachableprotects = disabled
restrictinfra = enabled
techlevel = 100 (max.)
techloss = -1 (no tech loss in this game)
victories = allied (no spacerace)

Then the city will be built on a mountain with a river plus iron resource (using the editor to find such tile, on a sufficiently large map),
also the city should be adjacent to a small lake (which is small enough, so that no second city can be built near it).
All units in that city will have *4.5 defence bonus up front and the iron allows to support tons of units (combined with factory+solar+Mfg.Plant) with zero pollution.
The city will buy these military/defence buildings: barracks, city wall, marine control center, SDI, SAM battery (no coastal fortress needed)
The lake tile enables it to buy AEGIS cruisers which get further boosted by SAM/SDI.
It will buy tons of (veteran) Mech.Inf. and several howitzers for active defence, which will take out any unit which encroaches the city immediately.

Ok, how would you ever conquer such a city?
Any spies will fail 100%, no marine unit can reach the fortress-city (because of citymindist-rule), all air units will fail because of massive
specialized defence (tons of AEGIS cruisers + SDI/SAM) and the city and its environs are 100% nuke-proof (SDI [=IronDome v2 ] )
And climate warfare is deactivated, too.

Ah i forgot something: the city will have tiles with zero defense bonus adjacent to it (the river starts in the mountain tile ^^).
Also the rule 'restrictinfra' negates any move-bonuses for attackers, so any units will have zero movepoints left, when reaching the city.
The city will also have air units to attack units some tiles away from it.

Your best bet is using Mech+Howies, but they get massacred right upon reaching the tiles next to the city.. a strategic nightmare for any attackers?

I bet any sum, that i would be able to survive with just 1 such city, versus a huge empire, led by ARAGO's mighty H.I.R.O AI player


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Edit:
Just recalled an even stronger configuration:
The city will now be situated on a singular mountain-island (with [unrealistic] river and iron, like before), in a lake (or tiny ocean) which has the shape of the (workable) city tiles (=20 tiles). Combined with 'citymindist'-rule this scenario now makes any land/sea-based attacks impossible (any Mech.Infs.+engineers which try to terraform the coast of the lake [to enable enemy to build a coastal city] will be attacked with air units from the central fortress city).
Only these units would ever be able to attack the city: stealth fighter, stealth bomber, cruise missile, helicopter and paratroopers (nukes get shot down 100% by SDI).
I believe, that this very configuration is uncrackable, and the lake/ocean (combined with city buildings) will allow the city to have lots of trade. And if the city additionally has these world wonders, it will be even more efficient: Shakespeares Theatre, Pyramids, United Nations, Statue of Liberty, Adam Smith's corporation, Magellans Travel, Apollo program, Manhattan Project (to buy nukes ^^).

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Edit2:
The accompanying scenario for your pleasure
Have fun!

What is "marine control center"? Is that aka Port Facility for building veteran naval units?

What is "ARAGO's mighty H.I.R.O AI player"? and how do I play against that?

Surrounding a city with a buffer of no-defense-bonus tiles is a strategy I have used in 1 city challenge games. Might take a lot of engineers a while to do the make-over, and you can't get rid of rivers unless you can transform them into ocean. To be extra safe you need 2 squares width because a 3 move unit (Armor or Mech) could attack on its 3rd move, but the city walls would defend against them. I have seen this work against the AI, one time a stack of enemy units appeared just outside the no-man's land and the AI knew enough to stay out, tho it could have moved a Mech next to my city and fortified it and then stack tons of other attackers with it, awaiting me destroying the stack with, e.g. a Howie. When I took out one of those stacks parked outside the no-man's land the message said "...destroyed along with 61 other units." Yikes

An enemy could use this method to break the naval defense:

1. Build lots of engineers.
2. Connect the lake to an ocean by using the engineers to selectively transform land tiles surrounding the lake into water tiles. Use 30-40 engineers for each tile, so that each transformation can be done within a single turn.
3. Build lots of battleships and relentlessly send them to attack the city.

A large empire should have no problem in producing an enormous number of engineers and battleships.

How do you handle the strategy of an enemy using engineers to connect the lake to an ocean, breaking the naval defense, and sending battleships to attack the city?

Embrace the unexpected aquatic warfare! Instead of fighting against it, turn the lake-to-ocean connection into an opportunity for a thriving maritime trade hub. Convert those battleships into floating markets, and watch your city flourish in the face of unconventional strategies.