If you have more leadership, resources, fuel and IC to build smaller, but stronger units, then i suggest:

* with Superior Firepower
- INF + INF + ART + ART + AC* - late AC will give them a lot of armor and toughness to reduce casualities at low fuel cost
- MED + MOT + SPART + SPART + AC* - i suggest quickly upgrade MOT to MEC

That divisions are stronger per width, but consume much more supplies per width, so they require strong IC to supply them with many supply techs to cover the same area like divisions in previous templates.

Overall players less likely uses 2 width tempaltes, because its harder to prepare with them stronger frontlines than with 3 width temlates, but dedicated armoured corps with 2 width units will be good choice to penetrate enemy lines with cumulated firepower on small space.

AI isnt a worthly opponent in hoi3, because it can't use the best templates, so we can counter that simple templates of AI. The best idea is to mix Tanks with Infantry with Artillery by lack of armoured threat and avoid situational support

* with Superior Firepower
- INF + INF + INF + ART + ART* is the most common spamable division. Build them as long as you need more units on frontlines
- MED + INF + INF + ART + ART* is a bit expensive, but good division that can win whole game for you. It doenst require a lot of technology and fuel, so even the smallest countries can use them
- MED + MOT + MOT + SPART + SPART* is low tech required fast armoured division
With better tech you can swap MOT with MEC

Heavy tanks are nice, but too expensive. spamming meds is more economical profiteable and do not drain your leadership for technology. Against players you may want replace one artillery with AT or TD, because they using armoured battalions much often. On tanks try to keep the best gun.

What about for early def inf

infantry korps, 3 divisions 2INF 2ART 1 division 2INF 1ART 1 AT 1 division 1ART 1AA, if you use 3 INF then only 3 divisions will be on the front with a width of 9, if you use 2INF in divisions all5 five will fit on the front, and with 8ART per korps you may see kill ratios even to 10-1 and it uses less manpower

whats your opinion on a counter to heavy tanks?

I usually mix 3 inf with either an AT, AA, or ART division, it allows more versatility without needing armor and such to reposition twice in the same month. Also, when I don't have air superiority I create a couple of dedicated AA (2 brigades) divisions to keep near the frontline or wherever the ennemy drop it's bombs (if the front is moving a lot, I also throw in a guard unit in case it ends up on the frontline)

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how do you make you divisions able to hold 5 brigades?

Thanks man

@oguzyurtcu44
If you let them fight in the desert against heavy tanks while lacking supply and being at constant bombardement: no
If you let them fight against other infantry-units: sure.

Especially when they fight in hill or mountain terrain. Sometimes you could even consider to attack light tank- (maybe even usual tank-) divisios in the Hills or Mountains. Of course it always depends on the situation, but usually theres no wrong in building 4 MTN. Maybe upgrade later with an additional MTN-brigade and equipment (as always: depending on situation and purpose of the division) .

Situation depends on: research capacity; industrial capacity; upcoming enemies; terrain; playstyle; supply situation;

The discussionstarter wrote, that 5 MTN would survive on its own, but i guess he would also only use 4 if he had not researched the "superior firepower doctrine" yet.