A couple barb questions

[Cheater Hater]

Having not played many games with barbarians on (since I like playing in my sandbox in SP), I have a couple questions, grouped into two main buckets:
1. Barb Progression:
I know the basics of how barbs progress (they start as animals, then actual units, then they research really slowly), but I don't know the actual steps, and how much they vary with game speed:

• When do animals appear, when do actual units appear, and when do barb cities appear?
  
• What determines how aggressive barbs are? I know there's a city threshold where they start entering borders (I think it's 2*num of players cities), but what determines whether they attack units or not? I've seen them suicide onto units, but I've also seen them not, even when not defending a city.
  

2. Barbs from huts:
I generally get this part, but there are a few edge cases I'm not sure of:

• I know scouts/explorers are safe to pop huts, and military units are unsafe, but what about city borders? What about Workers or Settlers?
  
• Is there a period where popping a hut with an unsafe unit can't produce barbs? Maybe before actual barbs show up?
  
• If a hut would have barbs and it's popped with a safe unit, is the hut fixed to a specific result, or is the result just rerolled?
  

Thanks for the info in advance

[WilliamLP]

Having not played many games with barbarians on (since I like playing in my sandbox in SP), I have a couple questions, grouped into two main buckets:
1. Barb Progression:
I know the basics of how barbs progress (they start as animals, then actual units, then they research really slowly), but I don't know the actual steps, and how much they vary with game speed:

• When do animals appear, when do actual units appear, and when do barb cities appear?
  
• What determines how aggressive barbs are? I know there's a city threshold where they start entering borders (I think it's 2*num of players cities), but what determines whether they attack units or not? I've seen them suicide onto units, but I've also seen them not, even when not defending a city.
  

This CFC thread is the best I've seen on the topic.

There are a few thresholds where they change character. E.g. you really notice the "NumCities > 3*NumPlayersAlive" one because it's when barbs suddenly start running the AI program to rush cities.

There's also a limit on the number of barbs on a landmass relative to the number of tiles which means you can actually be safe assuming certain islands will never have barbs on them. (Check Seven's PB16 thread for the details on this.)

A really useful point to know is barbs will never spawn within 2 tiles of a unit, even for tiles out of vision, so you can often place a unit such a warrior or scout in a place that makes it convenient because you can be absolutely sure you will never have to deal with a barbarian in the area.

[DaveV]

I know scouts/explorers are safe to pop huts, and military units are unsafe, but what about city borders? What about Workers or Settlers?

City borders will never pop barbs. Workers and Settlers can.

Is there a period where popping a hut with an unsafe unit can't produce barbs? Maybe before actual barbs show up?

I think I read once that you can't pop barbs if you haven't settled your first city. Of course, then you can't pop a tech, either...

If a hut would have barbs and it's popped with a safe unit, is the hut fixed to a specific result, or is the result just rerolled?

Barbs are eliminated from the list of possible results, and the odds are adjusted to make all the remaining results equally likely.

[Cheater Hater]

Thanks for all the help--that CivFanatics link is a really useful resource

[LexiSilva]

Yeah, CivFanatics can be a LOT of help! I use their info every day I play Civ.