The challenge in this map is not necessarily the 3 worst neighbors you can possibly have... remember that there are 3 other AIs out there somewhere... and they may be of even worse bunch... in a different way of course. ^_^
To be honest, as soon as I saw cooked map, though thought was "warmonger sandwich with peaceful AIs on another continent". The best ways to make such a map hard:
- make it reasonably likely for a stable religion on the other continent
- make sure each warmonger is likely to get "land target" to player
- make sure the foreign AI has lots of green land and luxuries to grow super large early
- make sure that the AI not nearby not only tech well, but also have similar peaceweights.
- allocate land such that one of the distance civilizations gets impossible huge (box in one AI on a peninsula to make sure another gets 25% land peacefully)
I don't have the micro patience of the old "super deity" players, but there have been some utterly brutal and deliberately unrealistic maps that have been won here

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Did you make a video out of that one? I seem to recall one where you settled way out towards Shaka on a hill and they suicided about 100 units on that city while you teched to rifles.
No, the game I was referring to was much older...IIRC it came from the time I was hosting IU.
Joao is a good candidate for distant AI, as are Zara, Justinian and Cathy. Traditional peacemongers like Mali don't expand quickly enough, and Joao will really gouge science after abusing his expansion bonuses.