I don't think it is
that stupid. Obviously, it would have been better to make sure he could not switch into slavery but that's crying over spilt milk. Attacking pindicator probably would have been a better choice, too. He has a history of belligerence with us, a legitimate casus belli, and, like you said, is focused a different direction.
But that doesn’t matter now.
Per game rules, can you ask OT4E for a city for peace? Is city gifting permitted?
Basically, you'd be saying "my bad, I don't want a destructive war but I also don’t want to let you off the hook for free.”
We definitely have the upper hand for now, just because of the element of surprise. We should press our advantage. Can he give us:
- Gold
- Gold per turn
- Resources
- Cities
?
We should be willing to compensate him (say 100 gold/ 10 gpt per city) but we should be aggressive. Maybe ask him to give us 100 gpt or something?
He left us with an opportunity and we took it. Unfortunately, there isn't the ability for us to make a "give us this city or we attack" offer. Also unfortunate that he switched back to slavery -- then you could have more easily threatened his cities in this way. But alas.
Anyway, the point of this offer is that he can get back onto his golden age and we can get back onto clawing ourselves back into contention. But we can press our current hammer advantage into taking some of his commerce. If not, we bleed him by pillaging and taking cities and workers that he leaves exposed.
You have, I think, perhaps made someone else able to win the game. Who knows? Maybe it's us? Are there other allies we can ask to enter the war against OT4E?
What is the damage of these ... 15 whips to his economy? Did he whip every city?
Obviously, not every unit will be able to reach the front lines and they're probably going to defend his core. But maybe we can move in and fork him? That reaction from him shows he's taking this seriously and that he views you as a threat. He's taking no chances.
So perhaps a diplomatic option will present itself?
If he doesn't accept the peace, that's all right.
Time to get some pistols and a doctor on site.
Not sure how we pay 'em in advance and treat him with civility. Maybe an intercessor can go out so we can have deniability? #hamilton
You have a brief advantage. Make the most of it. (Or not. It
is just a game).
But my only other piece of advice would be that: whatever you choose to do, do it
hard.
--
Addendum after your post:
He has knights only as long as he has horses. Can we attack those resources?