Many thanks for the positive feedbacks.
I wrote the guide during my first playthrough and had many change of idea in the meantime. There might be many forgotten/overlooked/wrong parts as well. I will correct them whenever I am directed in the correct path.
For now, my response to the above posts is as such:
@Sweynforkbeard
Going heretic is not my main plan for conquest but a tool I used during it. It has many useful applications and doesn't have much downside really. You can use it as much as you wish and you can convert back anytime. Also having lots of heretics has a very nice use... (such as granting them your demesne, granting them independence, starting holy war against them and invading and re-invading your cities. You can do it once in a few days, gaining ultra-fast gold..)
My main weapon for a fast conquest is "snatching (stealing) heirs".. Although I am surprised why people don't comment about it, but talk about crafting claims or "stealing claimants".. I've conquered 2 kingdoms in just 1 day without any real effort other than the cost of assassinating 2 kings + gifting 2 courtiers.. That's really a powerful tool.
I also won't be short on armies, because when you "snatch a heir" and get his lands for free, you get his levy ready too. That gives you a large enough levy very fast. Also as your retinue depends on conquered lands, you can easily go over 40-50k levy after 1000 holdings, which is enough for many occasions too.
Also a wrong religion penalty + heretic penalty won't matter when you're conquering real fast.
BTW, you can invade HRE with a 10 holding Duchy and a LOT of gold.. Or rather you can get a Duchy of HRE and purchase your way to the crown and get rid of the emperor and become an emperor fast, which I would prefer over an invasion.
Thanks for the archer tip.. After I learned about the skirmish units' superiority during assaults, I've decided to make a test on different units to see the minimum required days for invasion. (Although I used mounted troops mostly due to attrition limits.. But as I don't go conquering deserts now and chose to conquer most of the inland by sieging shore provinces, I might not have a problem with attrition..)
About Absolute Crown Law, I am thinking to have at least 2-3 empire laws and use them by instant-switching when necessary. (i.e. Suppose I have the Empire of Francia with Absolute Law and HRE with Medium Law. On the same paused day I can switch to Francia, banish everybody and re-switch back to HRE, without creating any discontent.. Cheesy, but works.. I explained this in TITLES section)
I also don't bother for Vassal gold, because it's really minor along Siege + Imprisonment + Demesne Granting gold.. But I might also use that for extra leverage. (Altough I tend to grant holdings to a few large Vassals to be able to summon large armies at any point on the world when I need them).
Thanks again. Really.
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@Joe_Chip
1- I didn't know that I could decide for the sons' educations when I make them a Duke. Will try that. Thanks.
2- For making a bishop, your point is taken. But in that case, I'll make bishops for all the unwanted rest and have to deal with only 1 heir.. (Not like my first game, where I had to kill half my heirs).
3- For educating the children, I suppose as long as you have some good diplomacy + intrigue stats, you can educate your heirs yourself. Otherwise, I'd prefer to educate them 6-11 years myself and let a very high stat guardian educate them 11-16 years.
4- You might be wrong about raising the levies of a Duke before imprisoning him. Because I did this many times and the levies didn't turn hostile (v1.091). (I also re-checked this now, and same result)
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@scelestus13
As stated above, for a low stat king (first generation), you can educate your heir for a few years yourself and let a guardian educate him for a few years. I have to make extensive tests about
a) During which years trait events pop up? Does it have a higher frequency for earlier or later years?
b) During which years the heirs gain more stats from their guardians? First 5 or Late 5?
etc.
But as testing these takes 10 years of gametime and even if I tried that with a totally conquered world (just to fast forward without any problem) this would require many hours to test a high enough number of heirs to get statistically meaningful results. I've really gotten old to try for such things :}