Race Relations
Relations are now tracked per race, making decisions about who you make war with much more important. Declaring war on an Elven city might give you a quick conquest, but dont expect your Elven citizens to be happy about it afterwards. As your relations with each race improves, you will be able to earn unique racial perks that boost your armies and economy as described in the Race Command Feature. However there are more benefits, like new ways of expanding your realm without warfare.
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Play Styles
People who expand through war will more likely to gravitate towards evil, while more peaceful players tend to gravitate to good. Players wanting to go all-out on either play style can choose the Keeper of Peace or Shadowborn specializations, which have been designed to augment good and evil play styles respectively.
As a peace-keeping player makes peace with various cities, their alignment increases and their race happiness increase. This in turn, increases the players relations with other independent cities making it cheaper to buy those cities and making it more likely that the cities will start offering vassalage for free.
A warlike player, on other hand, will tend to lose race happiness and alignment as they attack and invade more cities. This forces prices up and means independent cities are more likely to declare war on sight. The warmongering player must make careful use of the Migrate City operation to increase the happiness of their most important races, or face economic disaster.
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Impact
Using this system we have improved the alternatives to expanding through war. And we have synergized Race Relations, Diplomacy, Specializations, Independent cities and Alignment. You can vassal towns opportunistically, say in a quiet back land, to make it gradually develop while you spend your economy and military resources elsewhere. Its is also possible to release town you own as vassals. This gives relation bonuses, but it is also a way to reduce micromanagement in the end-game.