Sisiutil
All Leader Challenger
There are two main reasons to accept a vassal:Thank you both for the clarification. In my current game with Darius, I was at a situation where I needed to decide whether to capitulate an AI that was severely weakened after my war with them. I got an advice in that thread that if an AI was too weak and too small, it is pointless to capitulate them.
So I guess there is always the proper time and not-so-proper time to make a vassal out of the AI. I've always followed my own guideline at around 25% of my land and population as the guiding point when considering making a vassal out of AI. But it is nice to know that vassals can still win.
- Attack Dog: Vassalize a war-like AI (Shaka, Monty, Genghis, etc.). When you declare war, they are automatically at war on your side (this will help repair diplomatic relations with them, too). But I'm not a big fan of this type of vassal. The AI's effectiveness at war is spotty at best, even for the warmongers. They won't usually travel long distances to attack someone, so your Attack Dog will usually only live up to that name if he/she shares a border with your next target. Also keep in mind that the AI will pillage the enemy back to kingdom come, so if you're looking at conquering a civ with a lot of mature cottages, you're better off fighting on your own so you can preserve those towns and villages.
- Outsourced Research: Since you can dictate a vassal's research, you can have your vassal research techs you need and then trade for them. Obviously you want one of the better researchers in this role (any of the Financial leaders, Gandhi, etc.). You also want to leave them with enough cities in good locations to research effectively. Finally, you'll need to get on good terms with them, which can be a challenge if you've been kicking their butt for several turns.
I am not privy to the mechanics and mathematics behind this, but it seems very hit-and-miss. Based on my experience rather than familiarity with the code, it seems to happen more often based upon (a) the size and power rating of the vassal and (b) your diplomatic score with them. But even if your vassal is very near the break-free requirements, has a large army, and hates your guts, they'll still often cave and give you what you're after. DO NOT ever accept a vassal--voluntary or capitulated--if you know you'll eventually want to break the relationship, because it might not ever happen.Has anyone been successful at being able to declare war on your vassal by demanding all of the vassal's resources?