Let's start with a short distinction.
Early game /short games and late-game have totally different units which are useful.
Depending if you want to be strong in the early or in the late game, you will build different things.
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For early game / short games (first 5-7 days) main army composition:
1. Rocket artillery - Pretty much all starting troops have no armor or light armor. And you cannot even research-heavy armor (medium tanks) till day 2/3 (and medium tanks are slow to produce).
Now, it also sets Comintern as the single strongest starting doctrine due to early and cheap access to those.
But it also means you need to be VERY aggressive early, as when tanks become accessible and people start producing those, you will start lagging behind.
So conquer all you can before that happens.
They are so strong in the early game that in tournament matches you can see players producing 30 of those in the first 3 days and pretty much nothing else.
2. Medium tanks - Lots of early units are BAD against heavy armor.
And medium tanks are a great combination of heavy armor and attacking stats.
Get those.
They also counter best early strat of using rocket artillery, especially useful if you play in a tournament match against an active player.
Cons? Available day 2/3 depending on doctrine, long research, and long production.
But on the good side - They tend to scale well enough into late-game.
Doctrinewise?
Bonuses in Axis and Comitern - Axis ones are great when playing against active players due to speed bonuses.
Comintern are cheaper and faster to build, which makes them a good choice to stack into a lot of those when going against more passive players.
3. Tactical bombers - Hello Allies doctrine.
Only thing they bring to the table in the early game.
And a very strong thing.
Ally is a doctrine that is about having a wider array of units to your disposition, and hence possibly being able to better counter enemy. (Faster unit production also helps in this).
But that's not necessarily needed in the early game.
Tactical bombers, however, do work great early due to being able to both deal solid damage to non armored unit, as well as doing relatively well as a scout, due to solid range.
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Early support units:
4. A/A guns - Air control/defense is something you need.
It comes down to this or fighters.
And with fighters having penalties and having terrible scaling on Comitern, A/A guns are gonna be used way more often for early game rushers.
Mostly to defend artillery against tacticals.
5. Tank destroyers - This is very optional and worth it only if you have someone rushing medium tanks.
They are a valid cover unit for the early game.
On one hand, they are heavily armored, making the strongest early unit deal pretty much no damage.
On other hand, they are also countering medium tanks.
But again, those are mostly counters for people who try to rush early game.
Not much of a gain in themselves.
6. Armored cars - They discover stealth units.
That's it.
And you start with those too, which might be enough. Just upgrade them if the enemy has LVL 2 stealth.
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Now let's move to the endgame.
Balance of power moves HEAVILY.
Rocket artillery is nearly useless, as pretty much everyone has tanks and they scale terribly in damage.
Comintern itself also becomes one of the weakest doctrines, while Axis takes a lead.
Allies are still okayish in the late game due to the possibility of having access to more units types and easier adjustment to the situation.
But that requires a bit more knowledge of what you will be facing.
1. Fighters / Rocket fighters - Air control. Planes are still deadly.
Even more, than they were in early.
Late game people can have up to 80-100 planes easily.
Especially if you are playing against very high-rank players who know their values.
2. Tactical bombers / Offensive bombers
Airforce defines the late game.
It's fast, able to be redeployed on whichever flank you need.
And VERY strong, especially if your enemy is investing less than you into it.
Also allows you to scout into enemy territory.
3. Nuclear bomber - Ever heard of that 30 tanks stack your enemy has?
Oh, he forgot to add anti-air guns?
Just bomb it.
He did add anti-air guns?
Just bomb a province right next to him.
Unless he is in a center of the province, then too bad.
Well, that's the case, the pure existence of this thing can make the experienced player sit in the center of the province to not be bombed indirectly.
And yes, you can shoot a nuclear bomber down with anti-air if you are bombed directly.
Those things can stall the whole frontline from moving pretty much.
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Yeah, pretty much most of the endgame is about planes.
You can remove whole armies If you have air advantage.
So let me give you some ideas of what a good land army looks like:
1. 10 SP artillery / SP rocket artillery
7 armored cars
3 SP anti-air
Enough A/A attack to shoot down nuclear bombers.
Long range attack.
And speed to run away if you are around when the enemy tries catching you.
Plus you can catch stealth units.
And if you didn't know, up to 10 units can attack at once, so if you shoot, 10 artillery will shoot at once.
If you defend, your armored cars and anti-air will be defending.
Very good composition if you have no better ideas of what you will be facing.
Cons? Bit of low hp side.
2. 10 Medium tanks + 5 Sp Anti-air -
This is something for direct combat.
You can decide to detach A/A from the unit before you attack if your enemy has no planes nearby.
Fast, huge hp, heavy armored.
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Now those 2 compositions could be used in battles against high-ranked players mostly because they allows some transition from early units to the late ones.
On the other hand units like mechanized infantry could also be used, just require a bit more steps to achieve if you are transitioning from early units into the late game.
But to be realistic - in the late game, you mostly want to find a way to counter your enemy to the best of your ability.
So if you think mechanized will do better than medium tanks, just swap it for them.
You will even need fewer anti-airs since they have solid ones themselves.
Oh, and add some ships to fill the list up to 10.
That's it.
Sorry for the long post.
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Pretty good at killing infantry
subs to subversively spy on my next attack
