Hovershy

I've played with them a few times not much but generally they were never weak, but I wouldn't say like they were serious threats XD

Poland has a horrid AI, for me.

I was playing Germany once and I did all the European nations on the Europe map, and Poland founded new cities like it was going out of style but they were always at 0 gold and losing over -100 per turn with -22 happiness ._.

Zulu has great AI, though ._.