Bad make a calculation how much naq you would need to make 300 bils defences on planet.... (I ll tell you the approximation ...6-7 trills )
Then make a calculation how much naq you need to make a 40 bils (safe zone ) fleet (approximation 22 trils+ )
Now by your idea you would basically need 125 bils of fleets to destroy it...you want to calculate how much naq you need to make those?
( I ll tell you the approximation 200 trills )
You don't create Fleets/Fleet Hangars just to steal one planet, while the defenses you build on a planet are only there for one cause. So this costs you state don't show the actual picture.
My point is the following (an example) :
Theres a mine (of gold or whatever) which you want to have, but it is heavily defended by lets say 10000 robots with rockets - who are in the mine or around it. You only have 1000 of them with same weapons.
In order to destroy the defenders you need to bomb the hell out of them. But in the way they'r located, each time you attack you also destroy portion of the mine. Eventually the mine is basically gone, nothing to do there as everything is destroyed.
So this is where my suggestion of max attacks comes from.
This is even better in a way, cause if you take a planet with first attack it only loses 2,5% (or something) of its attribute.
Now it loses 25%.
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Lets see what can happen with the current system.
To build hangers for a 30 billion fleet it costs 14 trillion naquadah - about 53000 hangers. Fleets cost 650bil.
Total Costs: 14,65 trillion.
> If there is another war like COP vs CIA one, which lasts like 2 months.
Lets say we TL are in it against a very good opponent where one player has 30 billion fleets. 10 of us have 10 planets - each 300billion defense.
This ONE SINGLE player can make us damages worth 500-600 Trillion. Thats almost 1 BILLION Untrained Units worth. I doubt they would give more for repairs.
So yea guys, this system is perfect... Not.