Most feared/hated AI civ

[ZeitgeistGlee]

City spammers are definitely top of my hated list, Pocatello, Napoleon, Shaka, Alexander, etc. Nothing more irritating than seeing as nice bit of territory a few tiles from your capital only to have one of them plonk a settler on it when their capital is on the other side of the continent. Inevitably you're pushed into war early to clear them out otherwise you'll end up squeezed into a tiny little bit of territory with no growth potential. Worse still they have the audacity to covet what little territory I have left. Alternatively if you're on a islands map it means spending ages conquering all their far flung cities to take them out of the game. Alex's 1-2 pop polar cities are particularly vexing.

Trash-talkers with no ability to back up their words are more annoying than hated, often veering into amusing when I know they're completely worthless. Genuinely wish there was an option to laugh at them if they're completely pathetic.

Shaka is about the only one who gives me genuine pause when I see him spawn next to me, I almost always convert to military production and annihilate him (and/or bribe others to help) as quickly as I can before I have to face his legions of Impi. Other warmongers are generally more manageable by comparison.

 

[Keltainen]

Bismarck. It might be suprising, but in my games, he usually expands like crazy, and fight wars with only little provocation.

Early eras: O hai, I have more warriors than you.
Midgame: Landsknechts, Landsknechts everywhere.
Endgame: usually has taken over at least half of the world, and if not, he still has so high culture that my tourism isn't efficent enough - forcing me to go for the space victory because his army outnumbers mine.

Generally, the factions that priorise on religion are also annoying because tehy snatch all the useful pantheons and beliefs from you.

 

[Poopin Thelift]

Hiawatha. In one of my last games his empire of 70 cities (huge map, immortal) declared war after war on me. He had the most production of all civs all game long, and a tech lead most of the time. At the end I could pass him with a lot of RAs und Hubble, but he destroyed my Sience Victory (had to spend money on units instead of rocket factories). It ended in the usual DV allthough Hiawatha killed the half of my CS allies.