Should you attack a civ with twice as much units as you?

[akillias]

What is the threshold of sustainability in term of ratio?

 

[TheMeInTeam]

It depends on absolute size as much as relative, and game speed.

And tech....as well as how good you are tactically.

If you're talking about moderately sized civs, and not say 3 axes vs 6 axes with no siege involved, the answer is yes if you think you can win.

 

[colony]

It depends a lot on what units actually make up thes armies, if you have a small empire and Rifling against a big AI still using longbows then I'd probably attack. You need a lot of siege to really be successful in a war like that though. If they only have a similar sized empire and aren't too far behind in tech I'd be very wary of attacking, there are too many variables to give a definite answer.

 

[CynicalMagician]

If you're in a situation like that and you ~have~ to go to war, set up shop in a good defensive chokepoint city with some CG defenders and let the AI suicide a few stacks at you before you attack.

 

[Endure]

As others have said, there's so many variables its impossible to answer.

Do you have the tech lead? Are you beyond in tech? Can you bribe other civs into the war on your side? Is there a risk another civ will dogpile on you if you go to war with the first civ? Do you have some choke-points that can absorb the first invasion waves to help even out the numbers? Are you reasonably sure you can achieve your objectives (whatever they may be) in a timely matter and get out of the war before you start to feel it on the home front? etc, etc, etc

 

[Magma_Dragoon]

If you have cannons and your enemies don't, go for it.

 

[Unconquered Sun]

1 to 5 is still a good ratio when facing AIs who keep several units per city. The only units you should worry about are in the Stacks of Death, those you have to defeat.