Disclaimer:
I am not an expert on the history of the region. There may well be inaccuracies and imbalances in all this. Some small of them may be intentional for fun.
Please take easy for fun. 
Feature:
- This civ represents the kingdoms in the Kongo region (modern Congo and Angola).
- Livestock Markets use goats as default livestock instead of cattle animal.
- Each researched technology gives 1 goat.
- There are ways to accelerate early game influence income.
- Levied units are trained in a group of 5 units at a time at -15% cost.
- No desert outlaws but Jagas at Watch Towers.
Potential AI leader
Nzo Ukisi
- Literally āholy houseā, their Catholic Church.
- Equivalent to the Mountain Monastery and University. Can train Mestres and research alliance technologies here.
- Up to 1, and trickles XP instead of influence, but it has a holy aura about influence.
- Villagers and Fishing Canoes in the holy aura can generate influence when they are gathering resources.
(Gathering natural resources will generate more influence.) - Building buildings and training units within the holy aura can also get the influence bounty.
Mestre
- Healer unit.
- Trainable at Nzo Ukisi. With a bit higher cost of influence, and uses 1 pop.
- Has the holy aura too, but on a much smaller scale.
- Garrisoned in a ship or building can make the ship or building has the Mestreās holy aura.
- The train limit is 2, and +1 after hitting a new age.
- Literally āmasterā in Portuguese. Nobles, the kingās lay ministers, responsible for religious and educational affairs.
Default Technologies of Nzo Ukisi
- Cross Shaped Stone (I): Next Age up time -50 seconds.
- Religious Syncretism (II): The holy aura of Nzo Ukisi and Mestres become broader.
- City Walls (III)
- Saint Jamesā Day (IV): Receives crate of 10 XP and 10 coin for every unit; Levied units cost -15%.
Unique Military Units
Fidalgo
- Hand infantry hero with a great Cimpaba sword.
- Starts the game with 1 Fidaldo, and get 1 Fidalgo when hitting a new age.
- This is a term used by the Portuguese for noblemen in the army of Kongo.
Kimbaris
- Light infantry and foot Archer unit.
- Trainable at War Camps from age II. Costs food and wood, and uses 1 pop.
- Similar to the Jungle Bowman but with lower basic ranged damage and better poison damage.
- Kimbaris is the name of professional archer forces in Ndongo.
- The army in the Kongo region was mainly composed of levied archers. They used poisoned arrows to make up for the damage, especially in eastern Kongo. The bravest soldiers went into battle with only a few arrows, which were poisoned in some cases by a potent mixture called cabanzo.
Pombo
- Hand shock infantry with a club.
- Trainable at War Camps from age II. Costs food and wood, and uses 1 pop.
- As the scouting unit in Angolan states, sometimes ran with and kept up with horses, and also performed pursuit duties.
Adargueiro
- Hand infantry without the heavy or light tag.
- Trainable at War Camps from age II. Costs food and coin, and uses 2 pop.
- Expensive, having brilliant melee damage and ranged resistance.
- Literally āshield bearerā in Portuguese. The elite and most important troops in the army of Kongo, equipped with a long shield and a scimitar-shaped longsword.
Mambele Thrower
- Ranged shock infantry.
- Trainable at War Camps from age II. Costs food and coin, and uses 1 pop.
- With lower HP and higher attack than Eagle Runner Knights.
- Mambele is a general term for a type of throwing knife widely used in Central Africa.
Kanda Trooper
- Musketeer unit.
- Trainable at War Camps from age III. Costs food and coin, and uses 1 pop.
- Kanda literally means ālineageā which refers to the clans or houses that had powers and involved the civil wars. The name of this unit refers to the troops owned by those clans.
Mbanza Guard
- Skirmisher unit.
- Trainable at Palaces from age III. Costs influence, and uses 2 pop.
- The quality is average as a 2 pop unit, but it will be quite improved near the Palaces and TCs.
- Mbanza (ācityā) guards. According to some records, the provincial armies already had some musketeers in the early 17th century to protect cities and resist invasions, while Kongolese forces became accustomed to firearms in the 18th century.
Other military units
Jaga Spearman
- Outlaw heavy hand infantry.
- Trainable at Watch Towers from age II by default.
- Renamed from the current African Vagabond.
Jaga Archer
- Outlaw light infantry and foot archer unit.
- Trainable at Watch Towers from age II by default.
- With a high speed and a faster rate of fire than most foot archer units, good at hit-and-run.
Jaga Raider
- Outlaw hand shock infantry.
- Trainable at Watch Towers from age II by default.
- With a lance, it fights like the Lancer and good against infantry.
Jaga Knife Thrower
- Outlaw ranged shock infantry.
- Trainable at Watch Towers from age II by default.
- Renamed from the current Knife Thrower.
- Mercenary shock hand infantry.
- Similar to the Jaga Raider but stronger.
- Mercenary musketeer infantry.
- Very good at melee and siege.
- Uses an axe in melee combat.
Chokwe Gunner
- Mercenary counter-skirmisher rifle Infantry without the heavy or light tag.
Luba Bowman
- Native light infantry and foot archer unit of Luba minor civ.
- Cheap and weak but with a limit of 24.
Luba Swordsman
- Native heavy hand infantry of Luba minor civ.
- Powerful but slow, with a limit of 16.
- Looks like using a Ngulu sword.
Capuchin Missionary
- The renamed Inquisitor, with better stats.
Alliance
Portuguese
- Almost the same, just the number of Organ Guns is based on the number of Mestres.
Jesuits
- Just the same.
Dutch
- Blue Guards are available at Palaces.
- Dutch West Indies Company (II): Villagers gather natural resources 5% faster; Ships a Bank wagon.
- Protestant Influence (II): Villagers generate +8% influence in the holy aura.
- Yakas are available at Palaces.
- Sanguar (II): This Angolan martial art gives foot archer units and shock infantry +15% HP and attack.
- Flower of Angola (III): Ships a group of Gunzes (consulate Pombos) and Empacaceiros (consulate Kanda Troopers).
- Imbangalas are available at Palaces.
- Ritual Cannibalism (II): The Imbangala gets triple the bounty when killing enemy units.
- Plunder Bands (II): Ships 1 Imbangalas and 1 Cow for every 2 minutes, up to 30 minutes.
- Cows are available at Livestock Markets.
- Ovimbundu Trading Caravans (III): Trade Routes generate +100% resources; Native settlements give a trickle of 1 XP.
- Ovimbundu Crop Production (III): Villagers gather coin 20% faster and gather food 10% faster from farming buildings.
- Chokwe Gunners are available at Palaces.
- Lunda Immigrants (IV): Ships 1 TC builder; TC gets +1 limit; TCs automatically spawn Villagers instead of training them.
- Muslim Military Advisors (IV): Ships 6 Mamelukes; Mamelukes are available at Palaces.
Luba
- Luba Bowmen and Luba Swordsmen are available at Palaces and Native Embassies.
- Mining Monopoly (V): Ships 1 Copper Prospector Wagon for every 5 minutes, up to 1 hour.
(Also an age I tech of Luba minor civ.) - Ivory Trade (V): Ships 8 huntable elephants; Villagers can generate many coin and influence when gathering food from huntable animals.
(Also an age IV tech of Luba minor civ. The influence bonus would be changed to export if the civ is Asian, or to more coin if the civ is other else.)
Cards
The royal house series:
(Iām thinking of adding a limit like āonly one of them can be chosen to put on the deckā or āthe effect of the old house will go if a new house is arrivedā or something else, considering that this civ can gather influence easily. But maybe the limit is unnecessary.)
- House of Kilukeni (I): Ships 1 Mestre and 2 kingdom builders; Gives a trickle of influence; Costs 200 influence.
- House of Kwilu (II): Ships 6 Kimbaris and 4 Cannoneers; Cannoneers are available at Palaces (before allied with the Portuguese) and cost -10% (after allied with the Portuguese); Costs 500 influence.
- House of Kinkanga (II): Ships 3 Adargueiros and 5 Blue Guards; Blue Guards are available at Palaces (before allied with the Dutch) and cost -10% (after allied with the Dutch); Costs 500 influence.
- House of Kinlaza (III): Ships 12 Kanda Troopers and 10 Capuchin Missionaries; Capuchin Missionaries are available at Palaces and use -1 pop; Costs 1000 influence.
- House of Kimpanzu (III): Ships 10 Mambele Throwers and 5 Conquistadors; Conquistadors are available at Palaces and Native Embassies (before allied with the Jesuits) and cost -10% (after allied with the Jesuits); Costs 1000 influence.
- House of Ćgua Rosada (IV): Ships 1 Palace Builder and 16 Mbanza Guards; Palaces get +1 limit, +40% HP and +4 range; Costs 1500 influence.
The vasal state tribute series:
(Every one of them can make Villagers generate influence 2% faster in the holy aura.)
(Perhaps they should also have a cost and maybe even ship some crates or units.)
- Kongo shields (I): Fidalgos and Adargueiros get +20% HP.
- Vungu refugees (I): Villagers and Levied Spearmen cost -15%.
- Ndongo canoes (II): Ships cost -20%.
- Matamba axes (II): Pombos get +20% attack, and changed the wood cost to coin cost.
- Loango coppers (II): Villagers gather coin 20% faster from mines; the Mines last +100%.
- Anziku arrows (III): Levied Bowmen and Kimbaris get +25% attack.
- Ngoyo swords (III): Fidalgos and Adargueiros get +30% attack.
- Kakongo knives (III): Mambele Throwers get +15% attack, +4 LoS and range.
- Soyo guns (IV): Levied Gunners, Kanda Troopers and Mbanza Guards +25% attack.
Others:
- Manikongo (I): Fidalgo +50% hit points and attack; Fidalgo get a trickle of influence.
- War of succession (I): Fidalgos, Adargueiros and Kanda Troopers get +20% siege attack; the Kongo roral house cards cost -50%ć
- Traditional warfare (I): Levied Bowmen and Levied Spearmen cost changed to 50% influence and 50% food.
- Mestico musketeers (II): Levied Gunners cost changed to 50% influence and 50% coin; Kanda Troopers are trainable in the age II.
- Cabanzo (II): Kimbaris poison effect lasts twice as long and damage +25%.
- College of SĆ£o Salvador (II): Ships 1 Nzo Ukisi builder; Mestres cost -50%; Nzo Ukisi get +1 limit.
- Antonianism (I): Nzo Ukisi techsā cost -30% and research time -50%.
- Nzimbu shell moneys (I): Villagers and Fishing Canoes can generate more influence when gathering food from huntable animal and fish in the holy aura.
- Mpusu cloth moneys (II): Villagers can generate more influence when gathering wood from trees in the holy aura.
- Renda / Revenue assignments (IV): Villagers can generate more influence when gathering food and coin from farming buildings in the holy aura.
- 10 Capuchin Missionaries (II): Ships 10 Capuchin Missionaries; Costs 500 influence.
- 15 Capuchin Missionaries (III): Ships 15 Capuchin Missionaries; Costs 500 influence.
- Protuguese Firearms (III): Ships 10 Cannoneers; Levied Gunners, Kanda Troopers and Mbanza Guards +10% ranged attack; Costs 1000 influence.
- Dutch Firearms (IV): Ships 4 Falconets; Artillery +15% speed; Costs 2000 influence.
Maps
- Located south of the Congo Basin and Lake Victoria, west of the Swahili Coast.
- With rainforest similar to the Congo Basin and tree savanna similar to the Swahili Coast.
- 1 Luba and 2 Tswana settlements, or 2 Luba and 1 Nguni (Ngoni).
- Has a Trade Route.
- Between the Congo Basin and the Zambezi Basin.
- The overall style is similar to the Congo Basin, but filled with a lot of copper mines.
- 4 Luba settlements.
- Has a Trade Route.
Main reference (except hyperlinks above):
