Note: This was adapted from a concept made by UnitedWarriors with additional ideas from @NeonSunsets.

Skills

scavenging
fighting
farming
first aid
building
persuasion (for NPCs)
Note: it takes 2 training to level up a skill, each person can only have 2 skills

Scavenging

Level 1: 0-3 food, 0-3 materials, 0-1 medicine
Level 2: 1-3 food, 1-3 materials, 0-1 medicine
Level 3: 1-4 food, 1-4 materials, 0-2 medicine
Level 4: 2-4 food, 2-4 materials, 0-2 medicine, 0-1 item
Level 5: 2-5 food, 2-5 materials, 0-3 medicine, 0-2 items

Fighting

Level 0: 0-20
Level 1: 10-30
Level 2: 20-40
Level 3: 30-50
Level 4: 40-60
Level 5: 50-70

Farming (needs farmland)

Level 1: 1-4 food, 0-1 materials
Level 2: 2-4 food, 0-2 materials
Level 3: 2-5 food, 0-3 materials
Level 4: 3-5 food, 1-3 materials
Level 5: 3-6 food, 1-4 materials

First Aid (cumulative)

Level 1: heals slightly wounded (1 medicine)
Level 2: heals cough (1 medicine)
Level 3: heals wounded (2 medicine)
Level 4: heals fever (2 medicine)
Level 5: heals severely wounded (3 medicine)

Building (cumulative)

Level 0: build barrier (20 materials, 5 energy)
Level 1: build spear (5 materials, 1 energy), 5 arrows (6 materials, 1 energy)
Level 2: build shield (15 materials, 3 energy), backpack, club (8 materials, 2 energy)
Level 3: build axe (10 materials, 3 energy), bow (8 materials, 5 energy)
Level 4: build 5 ammo (5 materials, 1 energy), workshop (50 materials, 3 energy)
Level 5: build gun (50 materials, 20 energy)

Player Persuasion (for actions to npcs)

Level 0: 0-20 ally to group
Level 1: 10-30 ally to group, 0-20 ally to subgroup/impact stubbornness
Level 2: 20-40 ally to group, 10-30 ally to subgroup/impact stubbornness, 0-20 ally to person
Level 3: 30-50 ally to group, 20-40 ally to subgroup/impact stubbornness, 10-30 ally to person
Level 4: 40-60 ally to group, 30-50 ally to subgroup/impact stubbornness, 20-40 ally to person
Level 5: 50-70 ally to group, 40-60 ally to subgroup/impact stubbornness, 30-50 ally to person
Note: successful impact to stubbornness increase/decreases NPC's stubbornness by 1 depending which is desired

NPC Stubbornness (for actions resisting players)

Level 0: 0-20
Level 1: 10-30
Level 2: 20-40
Level 3: 30-50
Level 4: 40-60
Level 5: 50-70
Note: this increases with each persuasion attempt except when stubbornness is directly impacted

Threat

Level 0: 0 zombies
Level 1: 0-2 zombies
Level 2: 0-5 zombies
Level 3: 0-8 zombies
Level 4: 0-11 zombies
Level 5: 0-14 zombies
Note: each season this randomly either increases, decreases, or stays the same

Equipment (max 2 capacity)

Hoe (2): +1 food when farming
Backpack (0): +1 scavenging
Spear (1): +1 damage
Axe (1): +1 damage, +1 materials (+3 damage with shield)
Club (1): +2 damage
Gun (1): +3 damage (needs ammo)
Shield (1): -1 damage taken (premodern)
Armor (0): -1 damage taken (premodern)
Bow (1): +1 damage, -1 damage taken (needs arrows), can't equip shield
Book level [#] [skill],... (0): can be used to train a skill

Seasons

Spring:
Summer: +1 food from farming, +1 threat
Autumn: +2 food from farming
Winter: 0 food from farming, -1 threat

Events

Small Horde: +1 threat
Horde: Level 4 threat decides to attack
Large Horde: Level 5 threat decided to attack
Enemy Gang Attack: 1-5 level 2-5 enemies
Friendly Gang Aid: -1 threat
Civil War: All belligerents say /defend and are randomly assigned an opponent

Buildings

Barrier: +2 border
House: capacity for 5 residents, uses 5 border
Farmland: capacity for 3 farmers, uses 5 border
Workshop: capacity for 3 builders, costs 50 materials and uses 2 border, allows for building of level 3+ items

Zombies

Walker: 3 health, Level 1 fighting
Brute: 5 health, Level 3 fighting
Runner: 2 health, Level 4 fighting

Relationships (Friendship/Romantic)

Level 1: Acquaintance/Crush
Level 2: Mutual friend/Mutual interest
Level 3: Friend/Boyfriend-Girlfriend
Level 4: Good friend/Husband-Wife
Level 5: Best friend/Old couple

Commands (Your name)

/train [skill] with [other person]
Increases [skill] level by 1/2

/train [skill] using [book]
Increases [skill] level by 1/4

/scavenge
4*threat% chance of injury, 1*threat% chance of severe injury, if successful then bring back materials based on scavenging level and 20% chance of increasing scavenging level by 1/4

/farm
Provides materials based on farming level, 20% chance of increasing farming level by 1/4

/heal [person]
Heals person of all ailments using medicine, 20% chance of increasing first aid level by 1/4

/build [item]
Build item or begin the process using materials, 10% chance of increasing building level by 1/4

/equip [item(s)]
Equips item if player has room

/unequip [item(s)]
Returns item to group inventory

/scout [direction]
Tells you what buildings are [direction] of the base for reclaiming, 10% chance of finding 1-3 new people

/patrol with [2 other people]
4*threat% chance of injury, 1*threat% chance of severe injury, increases border strength by 3 (Border strength decreases naturally by threat level), 10% chance of increasing fighting level by 1/4

/bond with [person]
Increases relationship with [person]

/argue with [person]
Decreases relationship with [person]
Does not require the permission of the other person unlike most commands

/challenge [leader]
Attempts to begin civil war event, civil war event begins if there are more rebels than loyalists

/remain loyal to [leader]
Declare loyalty for leader when they are challenged, if more loyalists than rebels then all rebel leaders are killed and all rebel followers get -1 stubbornness

/fight civil war
Randomly chooses an opponent to fight

/defend
Defend the base from an attack, randomly engages with one of the opponents

/execute [person]
Leader only command to execute someone they suspect for treachery

/banish [person]
Leader only command to banish someone they do not want in the group

Example Person

<b>[Role]</b> [Name] [M/F/O] [Age 16-20]
[Skill 1]: [1-4]
[Skill 2]: [1-3]
Equipment:
Followers:

Example NPC

<b>[Role]</b> [Name] [M/F/O] [Age 1-30]
[Skill 1]: [1-3]
[Skill 2]: [1]
Stubbornness: 1-4
Equipment:

Example Day

Day 1: May 13, 2018
Season: Spring (1/2)
Event: None
Effects:

Food:
Material:
Medicine:
Threat: 2
Border: 20/20
Buildings: 10 barriers, 3 houses, 1 farmland

Inventory: 

North: ?
East: ?
South: ?
West: ?

Bulletin

The zombies have just been beaten back. It will take 2 more days until hordes begin to reform.
Don't forget that you have 2 energy!

Leader Wade M 18
Fighting: 2
Persuasion: 3
Equipment:
Relationship: 3 (Selina)
Followers: Selina

Fighter Selina F 18
Fighting: 2
Scavenging: 1
Stubbornness: 3
Relationship: 3 (Wade)
Equipment:

Farmer Bob M 16
Farming: 2
Scavenging: 1
Stubbornness: 2
Equipment:

Builder Ryan M 17
Building: 4
Farming: 2
Equipment: 
Followers: