Countryball personalities
USA: patriotic, boastful, rich, fat, thinks it's the best, kind to friends, generous (sometimes), likes freedom, likes guns
UK: sophisticated, likes tea, posh, honest, former colonialist, sometimes short tempered
Russia: sarcastic, likes vodka, kind to friends, rude to others, hates ukraine, narcissistic alcoholic 

There is a value, called "Relationship". One country may have a relationship with another of up to 100. The higher 2 countries relationship is, the more likely they will accept offers and co operate with you. The lower it is, on the other hand, the more likely they are to show aggression towards you. You may set the difficulty at the start of the game to determine how hard the AI will be. Only few countries are nuclear states. These countries may use their weapons of mass destruction in war.

AI, realistically determines how AI country acts

Dont use the thing where it prints when you press enter, dont use >>> at the start.