One thing I'd like in Civ4 is units that are truly invisible untill "discovered", like submarines, or special forces, or even spies/terrorists.
In order to make this work you'd have to make it possible for enemy units to co-exist in a tile (the submarine is under the destroyer, or the special forces are hiding in the bushes as the tanks go by).
But if they can co-exist in a tile, you need a mechanism for what happens if they're discovered in the same tile as an enemy. One possibility is that the strongest attacker in the tile automatically attacks the invisible unit. Then the next strongest attacker, etc. etc. untill the invisible unit is dead.
This would make submarines, and special forces more tactical in their use, and make detection units necessary. Additionally, I'm sure that having the option of true invisible units would open up some great avenues for modders.
As a corollary, if you have the mechanism in place for same tile battle resolution, you can use that mechanism as a way to model resistance.
If a town is in resistance, it has a percentage chance of generating an invisible "Resister" unit in the city. That unit can sabotage buildings, or attack a piece of artillery, etc, etc. As soon as a resister acts, it is discovered, and killed (or maybe there's only a percentage chace that it is discovered). There could be "Anti-Insurgent" units which are excellent detectors of invisible units.
Lots of possibilities.
In order to make this work you'd have to make it possible for enemy units to co-exist in a tile (the submarine is under the destroyer, or the special forces are hiding in the bushes as the tanks go by).
But if they can co-exist in a tile, you need a mechanism for what happens if they're discovered in the same tile as an enemy. One possibility is that the strongest attacker in the tile automatically attacks the invisible unit. Then the next strongest attacker, etc. etc. untill the invisible unit is dead.
This would make submarines, and special forces more tactical in their use, and make detection units necessary. Additionally, I'm sure that having the option of true invisible units would open up some great avenues for modders.
As a corollary, if you have the mechanism in place for same tile battle resolution, you can use that mechanism as a way to model resistance.
If a town is in resistance, it has a percentage chance of generating an invisible "Resister" unit in the city. That unit can sabotage buildings, or attack a piece of artillery, etc, etc. As soon as a resister acts, it is discovered, and killed (or maybe there's only a percentage chace that it is discovered). There could be "Anti-Insurgent" units which are excellent detectors of invisible units.
Lots of possibilities.
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