AI declaring joint formal wars, then don't do anything

[zxcvbob]

I've just started playing CIv 6 (vanilla) again. The AI have gotten a lot better since a year ago! But one thing I've noticed is that 2 of them will jointly declare war for no reason (early game, good diplomatic relations, and I'm stronger than they are) and then never send any units to fight. I generally use that as an opportunity to annihilate both of them, one at a time. I take out the weaker one first for the XP, then reinforce those veterans with my home guard and kill the other.

They will do the same thing in the late game, but the DoW is not so unexpected then. I think the farther-away one talks my neighbor into it, and they both expect the other to do the heavy lifting.

 

[seanos08]

Get GS as the AI doesn't seem to declare these no show joint wars anywhere near as often. In Vanilla I found that Ghandi constantly declared joint wars on me even though I was far away. I found it easier to make peace with his partner and stay at war with Ghandi so he can't make more joint war declarations. Also in GS there is a "join ongoing war" item in the diplomacy screen. If you do get attacked by a neighbour you can bribe another neighbour to declare war on them - but that is expensive and there is no guarantee your ally will actually attack,

 

[Victoria]

for no reason

The reason is very likely one if them does not like you and has paid the other one for joint war so they have more troops.
Remote joints ineffectual wars donseem to have reared their ugly head in GS as well.

 

[pkaem]

in GS as well.

Indeed. Just got one this afternoon. Map type should be renamed to "Async sausage" instead of pangea, I spawned on one of it's ends. I rolled eandom eleonora and got boxed in and dow'ed by punkass pedro. I was planning to horse him anyway so I chopped horse and didn't pay attention, killed him. Every body hates me, emergency defended, ok. Now every 45 turns china and mad mansa declare no show random joint wars from the sausages other end. Nothing happens since pericles holds mid sausage and hates everyone.