Using the "Barbarian Civs" aspect, "Barbarian World Challenge" and "Start as Minor Civs"...
OK, I know the easy solution is that I should just turn these aspects off, and I know I have complained about it in the past, but I wanted to show you an example of how incredibly overpowered this can be. There is also an issue of the player getting a HUGE overpowered boost by taking one of these civs after getting wiped out.
Game Report
I mean, come on.
It is 2260BC, and the game is without doubt already won by me, not due to skill but completely the result of highly overpowered random events. 
I am not really sure what the solution is here, but thought I would share. Maybe at least there should be some trigger that if a player takes over a civ that came from barbs, as I did, that the great general / golden age event can no longer be triggered?
OK, I know the easy solution is that I should just turn these aspects off, and I know I have complained about it in the past, but I wanted to show you an example of how incredibly overpowered this can be. There is also an issue of the player getting a HUGE overpowered boost by taking one of these civs after getting wiped out.
Game Report
- start game as Meiji, warrior as first build
- some minor exploring, two barb cities very close by... already see that this is going to be brutal and short-lived for the Japanese people...
- by about turn 10 or 12, the southern barb city becomes England, with about 4 spearmen and 4 warriors
- I can see my situation is completely helpless, and wait for my doom. England wipes me out maybe 8-10 turns later, and I take them over.
- with my spearmen army I effortlessly kill Carthage a few tiles to the east with my massive stack of spears. Everyone who hasn't been gifted stuff by the barb civ rules still has a force of 3 or 4 warriors at the most
- holy mama, I get the special "Golden Age" massive spawning event! It results in: the barb city to the SW becoming York and coming to my control; a force of three promotable spearmen and a ram spawning free in York; 6 promotable rams (one with GG attached), 3 spearmen, another unattached GG, and a couple other guys spawning in London; 3 rams and a promotable spearman spawning in Carthage; and on top of that a couple free workers and (I think) a free settler.
- see the attached picture
I mean, come on.


I am not really sure what the solution is here, but thought I would share. Maybe at least there should be some trigger that if a player takes over a civ that came from barbs, as I did, that the great general / golden age event can no longer be triggered?