Creature groups ==> Property ==> Economy ==> Money,Trade and Bounties ==> Profit!

User story: As a Player I want creatures to form different groups and be members of these groups. Like towns or bands.

I scheduled  the development of trade and basic economy (shops, money, rewards and bounties).
Research has shown that I need basic property to be fulfilled at first.
To make property game needs normal groups of creatures.
It leads us to current user story.

At first I have removed very old and outdated 'spawn zones' code. It was nice idea, but it resulted to be very awkward experience for player, so it stayed in game as a bunch of useless routines, eating up CPU time.
Once it was removed the peace has come to world of Fallen, because spawn zones were used to check friend/foe condition in most cases.
But not for long. I have returned friend/ foe recognition by using creature basic fractions, like necromutants, humans, wild creatures and so on.
War, war never changes.

Now I implement creature groups, the higher level of creature organisation, but!
There are a big of difference with old spawn zone system.
First, Creature may be a member of a group, but shouldn't be. Making every single creature to be a member of specified group is a bit of overkill.
For example, Necromutants don't care, do they members of 'mutants company of eastern forest'. They act according to their instincts and not group values.
It is no difference where have you met a Necromutant, their intentions are allays the same: Kill All Humans!
Because of this, most of non sapient creatures will use generic faction rules.
This decision removes a lot of burden to handle literally useless groups of mutants, roaches, rats and so on.

Second. As my previous experience shows, relations between NPC groups, unlike relations of Player VS NPC groups, should be as simple as possible, Reason one, game regularly check friend/foe relations between NPC and NPC, it may clutter CPU time with useless calculations. Reason two, too complicate relations between different NPC groups could be unclear and not fun for player.
That's why I have decided to keep groups relations on Group Values.
And values will have constant tables of friend/foe interrelations. Quick and simple.
For the first version of groups I'll use only one Value - "Law" and I think it would be more then enough for long-long period.
Groups of sapient creatures could be Lawful and Outlaw.
Table is:
Lawful vs Lawful = neutral;
Lawful vs Outlaw = enemy;
Outlaw vs Outlaw = enemy;

As I said, simple. Player would have more complicate relations system with these groups, but player is player.

It allows us to divide our sapient creatures (now humans only) into groups, like villagers of specified town or homestead and different band and ruffians!
Once I'll finish band, necromutants and roaches will not be the only 'meanies'  of Fallen.

Also, groups would handle property for creatures.
For example, some items would be in private property of specified creature, still they would be a property of a group and group will inherit stuff once creature will demise.