[PREVIEW] Divide et Impera 1.1 - Unique Supply System

[Litharion]

Divide et Impera 1.1 Preview - Supply System

Introduction
- Our aim was to design an entirely unique supply system for armies in the campaign. This adds a new layer of depth and complexity to the campaign map and strategy to army movement and placement.
- The basic way to describe the system is that armies will have to maintain supply lines to their home regions. These supply lines can be affected by many things including diplomatic relationships, sieges, seasons, etc. If the army loses the line of supply, that army will have to begin foraging for supplies. The various stages of supply lines and foraging over the course of turns come with more severe effects for the army. That army can even go into attrition.
- Various things are setup to help with the system, including supply carts, supply ships and buildings that act as supply depots.
- Navies also have supplies and must return to port to replenish them. Also, navies can act as supply help for armies to reinforce them with supplies while on campaign.
- The Barbarians and Nomads have a different system that is less based on supply lines and more based on region foraging.
- The AI is also affected by this system but not as heavily in some areas (because they simply aren't programmed to understand the system itself).
- Many aspects of the system are customizable by changing a few variables that are easily located. This includes the ability to turn on and off attrition for the AI.
- While the system is complex and will seem daunting when reading about it at first, it plays in a very intuitive way and fits very well into the mod. A full manual will be provided for the system.


The Basics
*Many images below come from a WIP version of the system and are not final in terms of text/effects.
- The script-based supply system offers a completely new gameplay mechanic affecting every army on the campaign map. It is now important to monitor the supply state of an army. Happily, this is done with next to no decrease in system performance.
- Every army with more than a single General unit on the campaign map now receives a supply effect bundle displaying the supply state. The current supply state is displayed under the army effects. Hovering the mouse over the supply icon will display its various effects and the current supply state of each individual army.

Spoiler Alert, click show to read: 

Regional Supplies
- Armies on the campaign map now need regional supplies to operate. Armies in a region reduce supplies based on the army's current supply state. Every region on the campaign map now gets a basic fertility rating that goes along with the regional effect bundles added in 1.1. The regional base food production indicates the regional fertility. These fixed values determine how fast a region generates supplies.

Spoiler Alert, click show to read: 

Overview of the region effect bundle:

You can see the Food/fertility level based on the food bonus:

Army Supplies
-Armies supplied by the local settlement will usually have a low supply consumption. Even unfertile regions will be able to sustain a local army for an unlimited amount of time. Stationing too many armies in a lowly supplied region, however, will decrease supplies until the region has no supplies left. Armies will then suffer from attrition.

Spoiler Alert, click show to read: 

- Armies in foreign territory have to forage for supplies, if no supply routes are established (See below for information on routes). The local supply consumption will be extremely high. The region will be stripped of supplies quickly.

Spoiler Alert, click show to read: 

Global Logistics System
- Sustaining supply chains is expensive, this is represented by logistic costs. Logistic costs raise upkeep and food costs based on the supply state of each individual army and faction-wide based on the number of armies connected to the supply chain. The more armies that there are connected to your supply chain, the higher the global costs to logistics and food. This is represented by a new faction-wide effect under faction summary named Logistics. The Logistic costs are updated with the current supply states of armies at the start of each turn.

Spoiler Alert, click show to read: 

Buildings and Units Overview
- Some new buildings and units were added to complement the supply system. Other (already existing) buildings are either required to establish supply lines or grant regional supply bonuses.
- Strategic Depots: Trade Ports and Storage Buildings function as supply depots for armies. Strategic Depots are necessary to establish supply lines into foreign regions (up to 3 regions away).
- Operational Depots: Granaries are reintroduced to work as operational depots, increasing the amount of supplies a region can store and granting a supply line into an adjacent foreign region.
- Farms/Grain Cities: These buildings increase regional supplies. Therefore, regions with farms can sustain more armies. As farms are spread across the whole region and not defended, enemy armies damage local farm buildings if they forage for supplies.
- Barbarian Baggage Train: Every faction with barbarian culture has access to basic baggage trains from every owned settlement. These units are customized based on the owning culture. Baggage trains, if attached to an army, grant additional supplies for a limited number of turns (varying for each campaign based on turns per year). A baggage train can supply armies even under harsh weather conditions and is vital for prolonged military campaigns. Nomadic trains gain additional food supplies from foraging (see the Nomadic system below).
- Civilized Baggage Train: Greek, Roman and many Eastern factions have access to supply trains from granaries, big trading ports and strategic depots. They grant a bonus to armies connected to supply lines by reducing logistic costs. A baggage train can supply armies even under harsh weather conditions and is vital for prolonged military campaigns.

- Supply Ships: Greek, Roman and many Eastern factions now have access to supply ships (merchant ships) from every port. Those merchant ships can carry vast amounts of supplies and are the best solution to supply forces operating on land. A fleet with a supply ship can supply nearby land forces until the fleet runs out of supplies. Supply lines by sea are generally less expensive.


Civilized Supply System Overview

Effect Bundles
- The civilized supply system offers many possibilities to manage army supplies.
- Local requisitions (open market): Requires at least neutral public order, dominant cultural influence and enough regional supplies to distribute. Army has to be stationed close to the regional settlement.
- Local requisitions (forced market): Low public order or minor cultural influence and enough regional supplies to distribute. Army has to be stationed close to the regional settlement.
- Local supply line: Army stationed far from the city. No enemy besieging or close to the local settlement. Enough regional supplies to distribute.
- Supply line 1-3 regions: Army stationed in owned region without regional supplies or in foreign region. An owned region within 1-3 regions with supply depot.
- Allied supply: The Army is stationed in an allied region and are buying supplies from the region. Requires allied faction without food shortage and high regional supplies.
- Seaport supply: The Army is stationed in a region with a major trade port. Local regional supplies are low. No enemy fleet blockading or nearby the settlement.
- Supply Line with Baggage Train: Supply lines with baggage trains can operate more effectively. A baggage train lowers regional supply use. Requires an army connected to a supply line.
- Army supplied by Fleet: Armies stationed close to a fleet with a supply ship in foreign regions are supplied by sea. Sea routes are cheaper and more efficient and can not be disrupted easily.
- Foraging (high/low supplies): If no supply option is available, the army has to gain all supplies to survive from the region by foraging. Foraging decreases regional supplies very fast.
- Attrition (no supplies): After all regional supplies are used the army will suffer attrition. Either moving into another (supplied) region or establishing supply routes can solve the issue.
- Supply cut summer: Some regions don’t support foraging during summer. If armies are not connected to a supply line, they will suffer attrition during summer. These include mainly desert regions.
- Supply cut winter: Some regions don’t support foraging during winter. If armies are not connected to a supply line, they will suffer attrition during winter. These include regions like the Alps.
- Military Logistics: Military Forces are supplied from your faction's supply pool. Every army connected to the Supply Chain will increase global food and logistics costs.

Supply Lines
- Supply lines are an exciting new feature of the supply system. Supply lines are established from your capital or from cities with strategic depots. Supply lines pass through friendly or owned regions between the army and the supply depot. Here is an example:

Spoiler Alert, click show to read: 

- Supply lines can only be sustained if there is enough global food available for distribution. The infrastructure needed to supply armies during campaigns is represented by logistic costs. Logistic costs rise with the distance to the nearest supply depot.
- Furthermore, regions on the supply line must be eligible, otherwise the supply route is blocked. Eligibility is determined by multiple factors including:

1. At least neutral Public Order.
2. No enemy army close to the settlement (blocking the supply route).
3. Region not under siege.
4. Not an alpine region during winter or a desert region during summer.
5. Region containing the strategic depot not out of local supplies.

Barbarian System Overview

Foraging
- Nomadic and Barbarian factions rely on foraging to get sufficient supplies for their armies. Factions with more elaborate logistics like Rome only completely rely on foraging if their supply lines are cut off or impossible to establish. Foraging, however, works the same for every army. There are 4 different foraging states based on the supply status of a region. The less supplies are available, the harder it is to forage enough supplies and the heavier the negative impacts on the region and on the army.

Spoiler Alert, click show to read: 

Effect Bundles- Nomads
- Nomadic armies live or die on their foraging abilities. Baggage trains inherit an important role for nomadic factions.
- Local camp supplies: Army stationed close to an owned settlement for a short period of time.
- Local camp supplies (low): Their life is constant movement and conflict. Nomadic armies get negative effects if they stayed in owned regions for too long.
- Foraging (high/low supplies): If no supply option is available, the army has to gain all supplies to survive from the region by foraging. Foraging decreases regional supplies very fast.
- Baggage train: The army is campaigning in enemy territory, supplied by a baggage train. A Baggage Train can provide enough food for the army in foreign territory based on seasons, but only for a limited amount of time.
- Attrition (no supplies): After all regional supplies are used the army will suffer attrition.
- Supply cut summer: Some regions don’t support foraging during summer. If armies are not connected to a supply line, they will suffer attrition during summer.
- Supply cut winter: Some regions don’t support foraging during winter. If armies are not connected to a supply line, they will suffer attrition during winter.
- Global Foraging: When fighting in foreign lands, a nomadic army lives or dies on its foraging abilities. Armies with an attached baggage train add food to the global food supplies.

Effect Bundles - Barbarians
- Barbarian factions are not capable of advanced supply chains. They have to mostly forage for supplies.
- Local supplies (high/low): Army stationed close to an owned settlement, with high or low regional supplies.
- Local land supplies (high/low): Army stationed far from the owned local regional settlement with high or low regional supplies.
- Supply Route: The Army is stationed close to an owned settlement in an adjacent region, allowing supplies in foreign territory. Requires at least low supplies in the owned adjacent region.
- Baggage train: The Army is stationed in a foreign region accompanied by a baggage train. The army won’t have to forage for supplies for two turns in enemy regions. After two turns the baggage train has to resupply in owned or friendly regions.
- Allied supply: The Army is stationed in an allied region, receiving supplies from the region. Requires allied faction without food shortage and high regional supplies.
- Foraging (high/low supplies): If no supply option is available, the army has to gain all supplies to survive from the region by foraging. Foraging decreases regional supplies very fast.
- Attrition (no supplies): After all regional supplies are used the army will suffer attrition.
- Supply cut summer: Some regions don’t support foraging during summer. If armies are not connected to a supply line, they will suffer attrition during summer.
- Supply cut winter: Some regions don’t support foraging during winter. If armies are not connected to a supply line, they will suffer attrition during winter.


Naval Supply System

Fleet Supply Effects
- Fleets are affected by the new supply system as well. Fleets can only stay on open sea for a limited number of turns (8). The supply amount affects campaign movement range and ship speeds. Fleets being on open sea too long will suffer attrition. To resupply fleets you have to station them in a port for at least one turn. Various effects can be seen here:

Spoiler Alert, click show to read: 

- to Turns left at Sea: Various effects based on time at sea.
- Port Resupply: The cost of resupply varies based on how long the fleet was at sea.
- Out of Supply: Fleets with no supplies are not only much slower but also suffer attrition.

Fleet to Land Supply
- Fleets with supply ships are able to supply nearby land forces. This is especially useful if armies operate far away from your territory or across the mediterranean sea. The images below show a scenario with a roman army fighting in spain supplied by the blockading fleet:

Spoiler Alert, click show to read: 

Seasonal Supply Effects

Winter
- Alpine passes: During winter all passes through the Alps are blocked by snow. It is impossible to establish supply line through the Alps and armies marching through the Alps during winter can be affected by winter attrition.

Spoiler Alert, click show to read: 

- Other regions have negative effects on supplies during winter. For example, foraging won’t be possible during winter in Germania for certain cultures.

Summer
- Desert Routes: During summer all routes through desert regions are blocked. It is not possible to run supply trains through these regions and armies might suffer attrition. All regions on the arabian peninsula are counted as desert region.

Spoiler Alert, click show to read: 

- Like in winter, some regions will affect supply routes in the southern and eastern regions during summer. These effects are based on the DeI seasons map (found in our Seasons manual).

[Butan]

[Ygraine]

Now you can't just send around armies everywhere & anywhere without planning and making sure you got supplies for your campaign.

[thomas_r]

I'll wait for the release of 1.1 but it seem complicated. I'm afraid that our armies will cost a lot now (I saw various +5 or +10 % upkeep cost, its huge ....)

I didnt understand the barbarian or civilised bagage train, it is a unit? a agent ?

I will wait for have a judgement, I prefer tried by myself

[Litharion]

I didnt understand the barbarian or civilised bagage train, it is a unit? a agent ?

It is a new recruitable unit.

[thomas_r]

Ok, so the question is, does the AI use it ?

Does this unit could go on the battlefield ? (if yes what are their stats)

[Master Necromancer]

Ok, so the question is, does the AI use it ?

Same Question and how does the AI handle it.

If the AI could use it efficiently than we could play pirate and attack enemy merchant ships!

Also isn't it better that the baggage train to be an agent?

[Principe Alessandro]

And if the army is garrisoned in a city what happens with their supplies?

[Ivan_Moscavich]

Same Question and how does the AI handle it.

If the AI could use it efficiently than we could play pirate and attack enemy merchant ships!

Also isn't it better that the baggage train to be an agent?

It doesn't.

And if the army is garrisoned in a city what happens with their supplies?

They are garrisoned and don't take supplies from a supply chain as they are supplied from the city themselves. They do still take a part of the global logistics cost though.

[Caius Bingerus]

with the words of a once wise old man: hoooooooooooooooooooooooly mooooooooooooooooooooly

[Litharion]

Ok, so the question is, does the AI use it ?
Does this unit could go on the battlefield ? (if yes what are their stats)

The AI could use it but we decided to not add the unit to AI recruitment templates because the battle AI is unable to recognize them and troughs them into combat. Regarding merchants ships, I might add them to AI recruitment templates as they don't cause issues on the battlefield for the AI.

[ra2z]

Will the AI be hindered aswell? rather have a seperate version if thats the case, its already annoying enough when playing smaller factions when you face constant stacks of AI armys since they can magicaly obtain cash to support and build them.

[VladoBlood]

First thing this is awesome i thank you so much litharion for creating this the hype now for 1.1 is 100% real ill be waiting for this even more than the naval overhaul as it will make my campaings so much harder and deeper and that is what i love about DEI more than anything else is how hard the campaign has become. (at least playing on very hard)
I read it all twice but i still have a couple of questions:

1).So will foragin be a completly new stance for armies? As this was not directly said i wanted to be sure.

2).Will the different cultures have different effects towards foragin then? Since like you said nomads live on these unless they bring baggage trains you would expect them to be more efficient in it or have less negative effects.

3).Will the seasonal effects be also different for different cultures? I would imagine for romans to have a hard time managing supply lines through summer in the dessert but would expect a faction, like say the numidians to have an easier time at it.

4).If i understood correctly the AI will be affected by the supply system but in lesser amount up to the point that they would not recieve attrition effects? I hope this is right cause i want the exp to be harder for me and not for the AI.

5). Why are you so goddamn awesome seriously?? This is the most important question i believe.

[karasis]

İt seems great!!

[DarkMatter223]

Amazing, very detailed and looks to add thought into expansion. Can't wait to get my hands on 1.1.

[Litharion]

First thing this is awesome i thank you so much litharion for creating this the hype now for 1.1 is 100% real ill be waiting for this even more than the naval overhaul as it will make my campaings so much harder and deeper and that is what i love about DEI more than anything else is how hard the campaign has become. (at least playing on very hard)
I read it all twice but i still have a couple of questions:

1).So will foragin be a completly new stance for armies? As this was not directly said i wanted to be sure.

2).Will the different cultures have different effects towards foragin then? Since like you said nomads live on these unless they bring baggage trains you would expect them to be more efficient in it or have less negative effects.

3).Will the seasonal effects be also different for different cultures? I would imagine for romans to have a hard time managing supply lines through summer in the dessert but would expect a faction, like say the numidians to have an easier time at it.

4).If i understood correctly the AI will be affected by the supply system but in lesser amount up to the point that they would not recieve attrition effects? I hope this is right cause i want the exp to be harder for me and not for the AI.

5). Why are you so goddamn awesome seriously?? This is the most important question i believe.

1. Foraging is applied automatically to armies not connected to a supply chain.
2. Yes, effect bundles are unique for each of the three different supply systems (Civilized/Nomadic/Barbarian).
3. Yes, seasonal effects are culture/faction based, germanic factions will not face the same problems during winter in their homelands as romans trying to conquer germania during winter. The same applies for numidians during summer.
4. The AI will recieve attrition just like the player does but it has some additional or free turns before it kicks in. AI attrition can be completely disabled by changing an easy to locate variable. A manual will be released together with 1.1 explaining how to disable it. Maybe a submod as well.
5. Thank you

[KAM 2150]

Just for those who worry about AI or increased difficulty. Fear not, the best thing about the system is that it is so natural, like it was always there Also due to some changes in economy and general campaign gameplay it works perfect 1000 years of shame and hard labour for anyone asking for submod to turn it off before evem trying it. Man up you pansies

[Dresden]

As it says in the preview, the system will appear pretty complex at first glance. That is because, well, it is quite complex and deep. But, that is a very good thing. Complex does not equal complicated and once you play the system and learn the various parts it is quite intuitive and really feels like it should have always been there.

The goal of our mod has always been to add complexity and depth to campaign play, something that we felt was lacking from vanilla Rome 2 at release. Yes, players have to learn the ropes in a lot of our systems before getting comfortable. But, we feel that makes for good gameplay and engrossing content.

Litharion has done an amazing job on this system. Obviously I am biased, but I think it is one of the most unique, interesting and advanced additions for Rome 2.

[Ivan_Moscavich]

Litharion, I think he was asking if foraging was a new army stance, not how it was applied.

And to answer that question, no. It is a buff/debuff attatched to armies like many other things in the game.

[The Roman Republic]

1.1 is looking to be a major update.

In regards to this I think it all sounds excellant, shame that it can't be fully integrated with the A.I. However a way to look at it is, isn't it making it harder for the player and easier for the A.I?