Battle plan

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A Battle Plan is an important tool that both help players to visualize how their army will advance, allows the AI to control the player's army, as well give the army a significant combat bonus (if on the offensive). Battle plans are tied to army commanders, each army commander can have one battle plan ready and a plan has to be drawn for each commander unless the player will give all orders to units manually.Most plans are fairly simple. If desired, commanders can also be given a complex plans with multiple separate orders so that different parts of the army can pursue different missions. Most players will find this rarely necessary, especially if they have a hands-on approach to their divisions, but the capability is there for those who like planning or have to coordinate complex operations.

An example would be a major invasion of Italy north of enemy lines to crush an enemy already engaged from the south. The player can set up and separately activate one or more amphibious landings, paradrops, and attacks by ground forces already facing the enemy, each at the time he thinks best. Some of these plan orders might be set up to be implemented (by the player at the same time, while others may be set up to occur in sequence, in each case activated by the player as needed by shift-clicking only on that specific order to activate it, and with the ability to change that element of the plan or the troops assigned to it before or after activation. This allows different parts of an army to perform separate tasks for the player within an overall strategy, much as army corps performed different missions for WW2 armies. Use of such complex plans is optional, but occasionally very useful when a player has to launch multiple different operations at the same time or by stages.

To make a battle plan for offensive land operations, the player must first define a Front Line – this is the point from which the army group will begin operations. Select the Front Line button or the hotkey z, then click on or draw a line on the map along a national border or the current line between opposing forces to indicate where the army's currently selected divisions will assemble. Then click the Offensive Line button (a line with an arrow) or the hotkey x and draw the front to which the armies should advance from the current Front Line.

Drawing battle plans[edit]

How a battle plan is drawn will affect how the AI will execute it. The AI will do what the battle plan tells it to do without question, so a bad plan can have terrible consequences. Here are the tools that the player can use to create a battle plan:

Naval Invasion[edit]

A naval invasion is an amphibious attack on enemy territory. It is a very powerful tool to open up new fronts against an enemy where he least expects them.

When selecting a naval invasion order, the player will be asked to left-click on a province with naval base as point of departure. There the army will gather for the assault. And right-click on the enemy province(s) to invade.

Naval invasions may be launched from any friendly port that the player has access to. This means that an invasion can be launched on enemy territory from the port of an ally that is not at war with the enemy.

Capacity[edit]

The total number of divisions assigned to naval invasions of a country is limited by its Naval Invasion Capacity.png Naval Invasion Capacity. The capacity is determined by the naval technologies of the 'transports' branch. The base value is zero, which means that the technology “Transport Ship” must be researched before divisions may be assigned to a naval invasion.

Year Naval Invasion Capacity.png Technology
1922 +10 Transport ShipTransport Ship
1940 +40 Landing CraftLanding Craft
1944 +100 Advanced Landing CraftAdvanced Landing Craft

The naval invasion order that exceeds with its assigned divisions the Naval Invasion Capacity will not take place. The arrow on the map appears but with the text “No divisions 0 Transports”. The assigned divisions keep their ! red exclamation mark which indicates that they have no orders.

Country's invasion capacity is measured in division number, not in their total weight or combat width. Wider and more powerful division templates allow to execute stronger invasions.

Preparation time[edit]

Naval invasions require time to prepare before they may be executed. The exact time it will take is dependent on technology and the amount of divisions to be shipped over. With the first level of naval invasion technology, a 1-division invasion will take 7 days and 10-division invasion will take 70 days of planning. Landing Craft technology (1940) halves time required.

The planning will proceed immediately, even while the divisions are still on their way to the departure port.

It is possible to prepare several invasions from different ports in parallel, even to the same target province(s), saving on total preparation time.

In the current version (1.4) planning time does not seem affected by unit weight.

Convoys[edit]

In order to ship units over to foreign lands, sufficient convoys are required to do so. The amount of convoys an individual division requires is dependent on its weight; the weight is equivalent with the amount of convoys require to ship over one division. The amount of convoys required is rounded up. Technology may decrease the amount of convoys required for an invasion.

Weight 0.1 0.5 0.7 1.0 1.2 1.5 1.7
Regiment
  • Support companies
  • Anti-Air
  • Anti-Tank
  • Artillery
  • Cavalry
  • Infantry
  • Mountaineers
  • Marines
  • Motorized Rocket Artillery
  • Paratroopers
  • Rocket Artillery
  • Motorized
  • Light SP Anti-Air
  • Light SP Artillery
  • Light Tank
  • Light Tank Destroyer
  • Mechanized
  • Medium SP Anti-Air
  • Medium SP Artillery
  • Medium Tank
  • Medium Tank Destroyer
  • Heavy SP Anti-Air
  • Heavy SP Artillery
  • Heavy Tank
  • Heavy Tank Destroyer
  • Modern SP Anti-Air
  • Modern SP Artillery
  • Modern Tank
  • Modern Tank Destroyer
  • Superheavy SP Anti-Air
  • Superheavy SP Artillery
  • Superheavy Tank
  • Superheavy Tank Destroyer

Naval Supremacy[edit]

In order to be allowed to execute the invasion, a country requires more than 50% Naval Supremacy (also called Naval Superiority in some tooltips) in all sea regions the divisions will need to cross in order to make a beachhead. Invading army will decline to embark on the mission with less naval protection.

Naval Supremacy over the region depends on the amount of ships on missions by the opposing sides, with a multiplicative bonus for air superiority. One fleet can simultaneously contribute to supremacy in up to 3 sea regions covered by its mission.

All ship classes contribute the same to the supremacy rating, a submarine being equal to a super-heavy battleship.

Ships on Hold or in ports do not contribute to the Naval Supremacy. Otherwise all mission types (formation spreads) contribute equally. Fleets on Patrol mission with Do Not Engage order contribute as well, even though they never engage in any combats.

Maximum possible bonus for Air Superiority is +100% to the ship amount, making each ship count for two. It is achieved when you have 100% air superiority and enough planes to cover 100% of the sea region.

Naval supremacy is only required for a short moment to launch the prepared invasion. After that the invasion will proceed even without sufficient supremacy.

Once the invasion has been properly planned, naval supremacy has been attained, and sufficient convoys are gathered, the plan may be activated.

Invasion in transit[edit]

Invading divisions travel through the sea province by province on convoys, and can be intercepted by enemy fleets and bombers just like supply and trade convoys. It is recommended to use escorts for the convoys, lest the enemy rally their entire fleet to intercept the invading fleet.

When invaders reach the shores and begin to disembark, the side being invaded gets a notification with an icon and a sound and has a brief moment to rally any defenders.

Invasion speed is improved by technology, and is greatly delayed by attacks on the convoys.

Invasion combat[edit]

If there are any defenders in the province where the invaders try to land, a land combat starts. As the troops land they need to unload from the ships first and this leaves them vulnerable to enemy fire, so they receive a hefty malus. Marines are special forces troops specifically trained for amphibious assaults, and receive a large bonus to compensate amphibious landing penalty.

Consider using Shore bombardment to support the invasion, as well as any close air support in range.

Post invasion[edit]

Unless invading divisions have captured a port or a city, they might be cut off from supply, and need to achieve these objectives within 72 hours before supplies run out.

Paradrop[edit]

A paradrop is an attack by air on enemy territory. A paradrop may only be executed by paratroopers and their support equipment. Divisions with any battalions that cannot be dropped may not be used in a paradrop. Most kinds of line battalions will make a division ineligible for air drops if they are present in the division; see the division designer display on whether the division is para-capable.

As there is no aerial supply system in HOI4, a supply source, such as a large city, a port or a connection to the main front should be established as soon as possible in order to avoid the effects of being unsupplied. It is advisable to land paratroopers in an area near a supply source and to quickly assault that source, as supply sources tend to be well guarded. Dropping atop enemy troops is an attack with hefty penalties and certain destruction if defeated unless the paratroops can retreat to adjacent friendly-controlled territory.

Air superiority[edit]

A paradrop, like a naval invasion, requires at least 70% air superiority in the strategic area the target belongs to. Air superiority is primarily attained by directing fighters to secure air superiority in a region, but (non-naval) bombing and close air support may help as well.

Transport planes[edit]

As with convoys for naval invasions, paradrop orders require transport planes in order to be executed. Contrary to other planes in the game, 1 transport plane does not represent 1 plane but rather a group of planes required to transport units.

The amount of transport planes required depends on the weight of the divisions to be transported. Paratroopers battalions weigh 0.5 and paratroop support companies 0.1. One transport plane has a carrying capacity of 2.0, and so could carry a division of 4 para battalions, or 3 para battalions with several support companies. If the air drop order planes total too little carrying capacity for the paratroops assigned, the transports will make several trips to ferry the paratroops, exposing them to more enemy attacks and causing the troops to arrive in separate waves.

Divisions need to be in a province with an airfield with transport planes in order to be able to execute the paradrop.

Front Line and Offensive Line[edit]

A player can either assign a whole country's border as a front line by clicking on the border or a player can assign a part of a country's border as a front line by holding the right mouse button and dragging the mouse over the provinces the player wants to belong to the front line deployment area. The AI will then move all the divisions into the position that the commander assigns to that front line. They are assigned either by having them selected when the front line button is clicked or added later by selecting them and Control-Clicking on that line. A player can also create several unconnected front lines and assign divisions between them, which may be particularly useful for a field marshal who may command an unlimited amount of divisions conducting various operations in different locations around the world. Divisions that are stationed at a front line that borders a non-ally will receive a planning bonus for their pre-attack preparation time. Front lines can only be positioned at a border, and the front line of battle between opposing forces counts as a border for this purpose.

From a front line, or from another offensive line, a player can draw one or several offensive lines or arrows that tell the AI how the player wants the selected plan's divisions to advance from the front line. The width and arc of the offensive line can be adjusted as described on the tooltip. If the mouse cursor is dragged over the offensive line or arrow the game will show the exact visualisation of how the AI will advance the divisions, step for step. ALT for edit mode and TAB to shift the arrow's base can be useful to direct the main effort.

The order to execute battle plans is given with the button above the commander portrait, along with a tooltip that provides information and advice from the staff regarding the battle plan. The AI then executes the battle plan until the troops reach their offensive line which has then become the new front line. If that front line has offensive line orders beyond it then the execute button has to be pressed again to resume the advance from the new front line. Pausing to rest, resupply, refit, regroup, and coordinate further plans was common between phases of a major offensive. This is also a good time to detach troops to consolidate control over occupied territory, which usually involves smaller divisions that specialize in discouraging unrest. The Garrison Area battle plan order is one used in such a situation.

Spearhead[edit]

Introduced in the Together for Victory paid expansion, the Spearhead order also starts from a front line and can be used alongside or instead of the Offensive Line within an army. Unlike the normal battle plan that spreads out to cover its flanks and adjusts to circumstances, Spearheads advance in a narrow path one province wide to their objective, exactly as it was when first defined. This makes them suitable for blitzkrieg-style armored penetrations that can capture a specific goal or work with another spearhead pincer to encircle enemy cities or armies in pockets, sealed in a ring of steel by the mobile and regular infantry divisions following behind. Encircled armies can thus be annihilated, as routed divisions which lack friendly territory to retreat to are destroyed.

Spearhead (shortcut 'B') may be used only through territory past the attacking army's front line or territory assigned to a naval invasion (tanks rolling off the landing craft into battle). Spearheads follow the exact paths traced on the map by right-clicking and dragging the mouse through successive provinces. This may enable the attacking forces to plan a path that bypasses forts, cities, or other undesirable terrain in order to maintain their momentum.

Fallback Line[edit]

The player can draw fall-back lines in controlled territory, and that will tell the AI upon order execution to move and deploy its divisions behind the fallback line in the same manner as with a front line, hold the line against enemy assaults, and counter-attack to restore the position if the line is broken. Unlike front lines, divisions stationed at fallback lines do not receive a planning bonus; however, divisions that are stationed a long time in a province can accumulate an entrenchment bonus while remaining in that position.

Garrison Area[edit]

This assigns the entire army to guard an area rather than a front line. It is mainly useful for divisions on antipartisan duties or to protect against paratroopers. As the divisions are spread out over one or more states rather than concentrated in a position for defense, this posture is ill-suited near the front line.

The garrison command has multiple subsections; Protect Victory Points, Guard Ports, Guard Coast, Guard Forts, Protect Airbases, and Attempt to Lower Resistance. The player can choose which of these he wishes to guard and the UI will tell the player how many divisions the AI considers necessary to satisfy the command. Reducing resistance is best accomplished with an army of security divisions. 2-6 Cavalry battalions plus Military Police make effective security divisions, and require only minimum weapons and training. A very different type of garrison division is a static division intended for positional defense - its purpose is not to do damage but to entrench and hold as long as possible against enemy attack to provide time for relief to arrive. ORG, DEF, and entrenchment are important, as is piercing enemy armor. This division can be trained infantry with basic weapons, Engineers for defense, and a battalion or company of AA guns (which help against air attack, can pierce light armor, and don't need tungsten to make) or AT guns. It will be fighting alone, so combat width is not important.

Planning Bonus[edit]

Each division that is part of an offensive battle plan will receive a combat bonus known as a Planning Bonus that will grow up to a limit (starting cap is 50%) as long as the division remains stationed at a front line with an offensive order. The planning bonus will start to decay if the division is fighting, moving or is not stationed at a front line. Both the max planning bonus as well as the speed the planning bonus grows at (planning speed) can be increased. The Mobile Warfare doctrine has a very quick planning speed while the Grand Battleplan doctrine can get a very large planning bonus if given the time. The closest defensive equivalent to the planning bonus is entrenchment. The planning bonus is also closely related to organization. Both grow as the division rests, and both decay as the division moves or fights.

Manual Control and Battle plan; Support Attack[edit]

Manual control follows the same rules for the planning bonus. The battle plan system is not made to be a replacement for manual control but rather to take care of much of the tedious tasks such as garrisoning an area or placing divisions behind a river. Divisions that belong to a battle plan and receive a manual order will after fulfilling the manual order revert back to AI control. Once combat is joined, the player may select an unengaged division and then Ctrl+right click (or Ctrl+alt+right click) on the combat icon to make the selected division join in a support attack (a familiar concept from previous HOI). A support attack assists but does not automatically advance the division into the enemy-occupied area upon victory. See the combat icon tooltip as a reminder. Battleplanner may automatically order such a support attack if it determines it to be appropriate to join it as support. Review the tooltip. If a division is manually moved up and left without further orders, battleplanner may decide to use that unit.

As the planning bonus is granted even if the plan is not executed, micromanaging the entire army is possible without losing out on the bonus.

Battle Plan and Allies[edit]

Players can see their allies' battle plans (an option that can be toggled on and off in the lower right corner of the screen). This may help in multiplayer to coordinate with allies and in single player to understand what the AI is doing because AI countries create their own battle plans.

Creating Plans With Encirclements and Armored Spearheads[edit]

Main article: Armored Spearheads

Made easier with the Spearhead battle plan, the battle planner in HOI4 can be used to create plans that will mimic decisive battles in WWII, such as the Battle of Kiev (1941) with well over 700,000 in Soviet losses or the loss of 61 Allied Divisions during Fall Gelb.

There are various ways to accomplish this with the battle planner, but a basic pre-Spearhead guide is available here.