Games

Economy abridged: infrastructure determines construction speed and some aspects of supply, the number of civilian factories and your trade and economic policies determine how much “construction power” is added to the queue every day, the number of military factories and resource availability determine how much equipment is produced every day, and dockyards work similarly. This can all be abstracted as ‘IC’ or Industrial Cost. If you are a big spreadsheet person, some people define their army divisions in terms of equipment needed and calculate their economy in advance. Civilian factories are the currency for trading resources. You can also do things like build fuel reserves and import a bunch of oil before you know there’s going to be war.

Army abridged: technically there are optimized meta divisions for every single terrain and combat width, and you can look those up. That really only matters in competitive games between humans. Basically, infantry holds the line and armor pushes. Infantry divisions are bricks of HP, organization, and soft attack that resist the enemy in place. Line infantry is usually 10 or 20 width with at least engineer companies and support artillery. Port garrison infantry is 10 width with engineers. Assault infantry, if you really have to, is 20 or 40 width with line artillery and any breakthrough you can get. Line artillery has been kinda bad for like five years. Paratroopers are a waste of time unless you can get air dominance and want to try to insta cap a country by landing on every city. Unless you need to naval invade something early, Marines are best with amphibious tanks and amtracs. Mountaineers are infantry+, and you should use them instead of assault infantry (if you have to). Armored divisions are broadly bricks of armor, breakthrough, and soft attack that rapidly beat the enemy. The balance is that tanks alone have poor organization, so you add motorized or mechanized or cavalry. The slowest battalion sets the division speed. Anything less than 20 width is waste of industry. Light tanks are a tool for an early war, especially an early offensive war. They are quickly outclassed by mediums. Heavies are slow and the AI isn’t very good at piercing armor, so they aren’t really worth the cost. Things like self propelled anti air or artillery are really only good as an expensive unit for infantry. Adding armor reduces damage taken, more or less. Basically you want at least 30 organization and as much armor and breakthrough as you can get. A 7/8 split of tanks and whatever else makes a decent 30 width unit. You want logistics, maintenance, and engineer companies with them. Motorized divisions are not very good, but they can be used to exploit armored breakthroughs and some countries start with the units. Mechanized divisions are incredibly expensive infantry, but if you can afford them it’s fun. The strategy is something you’ll have to develop for yourself, but remember that you can pause! Pause literally whenever you want, especially when you are at war. Things like river lines, forts, and mountains are easier to hold/ harder to attack. The most effective way to inflict casualties is encirclements, which can be as small as one division pocketed by two tanks going to either side of it. The most effective ways to experience casualties are to try to mass push with infantry or to have one unit extend deep into the enemy for an encirclement. The question of who is encircling who can flip very quickly. Support companies are really fun for customizing your play style, and the only bad choice is military police on a front line unit.

Air abridged: air is probably the most important feature of combat in Hoi4. This could potentially be traced to a broad Western overemphasis on the role of the USA in the European Theatre of WW2, but that’s besides the point. Luckily it’s not that complicated, cause you just want your air zone to turn green, which gives your units buffs. You’re going to want to build a pile of fighters, and the key to victory is destroying your enemy’s pile of fighters. You only need a few hundred bombers, but you might need thousands of fighters. Also, if you are a tiny country with like 10 military factories, just build AA for your units instead of planes. You should never have fighters engage unless the numbers are relatively equal. There’s a degree to which you can make up for numbers with more advanced planes, but not much. If your fighters have been beaten down to the point that the enemy has twice as many as you, ground them and wait to build more. They will be shot down if you send 500 fighters against 1000. CAS are frankly the best bombers, and they can hit railroads, trucks, and enemy units. Tactical bombers are more expensive and less good, but they have a jack of all trades thing. Strategic bombers are mostly ineffective unless you are the USA and you start building them in 1938 so you can blot out the sun. Naval bombers are really good at killing submarines, convoys, and other coastal ships. Air superiority and some type of bombing are the only two air missions that matter. Interception is for intercepting a lot of enemy CAS or bombers, which shouldn’t happen if you have enough fighters. Basically, achieve air superiority with your fighters (‘green air’), and then place bombers on areas of crucial combat or where the enemy has logistically overextended (you can bomb their supply trains and trucks).

Navy abridged: famously no one cares about navy in hoi4. You can win most everything without ever really thinking about it. That said, the basic rules are submarines are good, never mix subs with anything else, and have at least 4 screens for every capital ship in a fleet (the ones with a diamond next to it). The AI either doesn’t research or doesn’t effectively build destroyers or cruisers with sonar or depth charges. As such, about 100 Submarine 3s set to always engage can destroy every single surface ship in the Atlantic in a year or two, as long as you have fuel. You can also build naval bombers and win naval battles the easy way (picking them apart for weeks before smashing the bleeding remnants).

Sorry if this is like incomprehensibly long, i have a lot of hours in the game