When fighting in the jungle in Hearts of Iron IV, it can be a pretty daunting task, so to keep your world domination ongoing, I’m here to provide some tips and some ideas.

Tips:

• Keep your units well maintained and supplied by providing a clear supply point and railways.
• Always ensure your units are not moving at a slow speed. Your goal is to encircle enemy forces and maneuver past them, as facing them head-on is a recipe for a protracted war.
• Ensure adequate numbers of equipment remain ready for use and are continuously produced, as tons of equipment will be lost due to attrition in the jungle.
• Ideally, keep a not-so-supply-heavy unit in jungle terrain, as supplies here are precious and you don’t want to bog your troops down.
• Avoid motorized and armored units here, as they suffer a movement penalty in the jungle.

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Now, we’re going to discuss the top five units and the top five best division templates for dealing with jungle warfare.
 

Top Units:

Bicycle Infantry

Bicycle infantry, as defined by the title, are infantry on bicycles. They’re basically the faster kind of infantry, as they can also outpace regular infantry and cavalry units.

Why they are good for the jungle:

• They have the fastest speed without any kind of jungle debuffs
• When paired with an infantry general, they do pack quite a punch
• They do not require as many supplies as other units here

However, it should be mentioned that bicycle infantry require support equipment to train, so keep this in mind in case you are unable to maintain production on this equipment.
 

Cavalry

Cavalry units should be the basic unit for any jungle attack or maneuvering.

Why they are good for the jungle:

• They are cheap to produce, only needing infantry equipment
• Contains the same soft attack for regular and bicycle infantry, thereby acting as a good stop gap option
• Has a high organization, allowing your troops to stay in battle for longer periods of time

That being said, cavalry units contain the same speed as regular infantry, so it may be possible to swap the two for one another in case you want to take advantage of your country’s national focus.

Paratroopers

Paratroopers are a specialized unit and can only be produced in limited quantities. Still, if you have any inkling of war, you know that paratroopers can significantly change the outlook of the battlefield.

Why they are good for the jungle:

• They can be used to cut off the enemy's supply routes or flank them in jungle terrain, making their lives a living hell
• They have a high level of organization, which allows them to hold a point for as long as possible 
• They can be equipped with support companies and other brigades, allowing them to be much stronger while also bypassing the terrain debuffs for jungle terrain as they will be airdropped instead of just marching through the land.

This is a fairly niche pick, as you require transport planes and many other support companies to truly utilize the full capabilities of a paratrooper division, but in the right hands, they can be quite deadly.

Close Air Support

Close Air Support planes have a single goal: provide supporting fire to your troops in battle. Think of them as mobile artillery platforms.

Why they are good for the jungle:

• They can easily tear apart the enemy organization, allowing your troops to quickly end the battle in your favor.
• They provide buffs for any allied ground forces during a battle (apart from the aforementioned air support)
• They can be easily produced provided the player has the right design companies and national focuses (i.e., air production or air-related focuses)

The aim of the CAS in the jungle is to provide extra attack to your troops and help in tearing the enemy organization apart so that you can occupy their tile as soon as possible and launch another attack while they’re still not prepared.

Transport Planes

Transport planes have only one goal: to deliver supplies through the air.

Why they are good for jungle:

• They can be used to supply your troops in the jungle without requiring a supply depot.
• They are also essential to any paratrooper mission.
• They can be attached to armies to basically serve as their flying cargo carrier.

A major downside of transport planes is that, when supplying an area, they require constant CP to perform their mission, so having too little CP would mean some areas cannot be properly supplied.

Top Division Templates:

It should be noted that while these templates can work in attacking jungles, you should never forget to neglect air support and proper supply management; otherwise, none of these templates will even work.

The Basic Cavalry Template

Why this template is great in the jungle:

• They are easy to train, and their equipment is easily producible.
• They have a low supply and demand, allowing you to put more men in one tile.
• Resupplying this division is simple as they primarily require infantry equipment.

This template is a basic cavalry attack and, while useful, should not be the main driving force of your army unless you are a really minor power and need to preserve your units as much as possible. Again, the goal of this unit is to strike fast and encircle the enemy as soon as possible.

The Upgraded Cavalry Template

Why this template is great in the jungle:

• They contain a strong soft attack and should be able to beat back any enemy infantry divisions in the jungle.
• They have a fairly reasonable supply and demand, again allowing for more units to be placed along the front.
• Their combat width of 18 is the best for various terrains and should fit well during any battles.

An upgraded form of the previous template, this division should be much better at attacking the enemy in jungle regions and outflanking them. The main advantage of this is the addition of logistics companies, which prevent supply and demand from going much higher.

The Basic Bicycle Infantry Template

Why this template is great in the jungle:

• A higher defense than cavalry units provides additional breakthrough to this division, allowing your men to try and penetrate the enemy defenses directly.
• They have the lowest supply demand out of all units and work extremely well in the jungle, where logistics is a nightmare
• Given the many terrain adjustments, they can do the right damage with the right commander, national focus, military high command, and design company.

The attractive part of this template is that given the right bonuses, commanders, and focuses, it can work much better than originally portrayed. Still, even without that, this unit can work in a large amount as the supply and demand of this template remain significantly low.

The Better Bicycle Infantry Template

Why this template is great in the jungle:

• This template is fairly strong as, it  has a greater amount of defense, breakthrough, and soft attack.
• Their supply and demand remain amazingly low, which will allow your troops to attack at full strength.
• A strong organization will ensure that the troops keep fighting until their dying breaths.

If your goal is to remain fast while doing a good amount of damage, you would be better off using this template, as given its 9 infantry composition, you can inflict a large amount of soft damage on the enemy, enabling your troops to quickly finish the battle and occupy the enemy position as soon as possible.

The Paratrooper Template

Why this template is great in the jungle:

• They can do quite well in outflanking and cutting off the enemy’s supplies as they contain a strong soft attack, defense, and breakthrough.
• Their supply demand is not as bad as some others, and they can be resupplied through the air.
• They have bonus speed in the jungle, which is always beneficial as the plan is to get to the location before your enemy.

If you plan to use paratroopers, it’s best to ensure that they can both attack the enemy and hold the territory they take for as long as possible, and with this template, you can expect to accomplish both. Additionally, if supplied with transport planes, this template can even emerge as an attacking force against any enemy units, even if your paratroopers are surrounded.

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