To figure out how to fight against a faction, the really best way to do it is to play as said faction and realize its limitations.
In the matchup against ECA, 3 factors come to mind :
- Map
- ECA's strat openning.
- Your goal.
Maps that often have 3 lanes , are easier for ECA to play on compared to maps that are completely open ( Lagoon vs Forgotten Forest) . Supply distances also matter, playing ECA on maps like Dust Devil against fast factions is often a very unfavorable matchup to them. Try pickig different types of maps and fighting the same opponents on those unfavorable maps.
If ECA starts with a warfactory then you should be expecting harass early on, followed by a faster tech rush. It's very possible to see tigers flying around very early on. This oppening does leave ECA with only 2 dozers to play with, which loosens up their grip on the map usually.
If an ECA is openning up with 3 dozers, then assume that he's going to have a stronger map grip. If you're USA then you can relax alittle bit since any early harass from this openning is rather too inefficent ( bloodhound and 2 felins hunting an osprey is rather too expensive). China wouldn't worry as much, meaning that the 2 factions that should keep their guard up is Russia and GLA , for supply protection against an early bloodhound. Rest assure that if you manage to fend it off, ECA cant really do much other than that.
Always have some AA with you to fend off tigers, around your base , supplies and army. A mix between T0 infantry AA and light AA vehicles is often optimal. If tigers reaching critical mass, then tech up to tier 2 to get the heavy AA up.
Other than tiger harass, there isn't really much ECA can do besides their usual basr crawling. Keep your senses up, the moment you hear a howitzer shot, your eyes on the marker and your finger on the "X" hotkey, to scatter your units away from the bombardments. Keep in mind that the more howitzer shells easted , the more room you have for your artillery to demolish ECA's defense lines without retaliation.
If ECA go ground units, other than pandurs ( OP unit) there really isn't anything you should fear.
Ofcourse keep your scouts around the map, to see any 'unexpected attack" . Alwayd have some heavy anti infantry units to counter a Mechanized Batallion attack.
When attacking a defense line, you want to do 2 things, habe combined arms as well as focusing on a specifix type of defense. ECA's defenses are specialized, meaning if you wipe 1 type of defense from the position, then thst position is pretty much yours.
For example, mixing alot of basic infantry with your tanks and focusing on either guard towers or Fortifications/Gun turrents. When one of those are removed, move back the units that are weak against the remaining defenses , and just slaughter the rest with the ones that hardcounters their remaining emplacements ( moving tanks behind after killing guard towers and letting your infantry take care of the rest). This lets you minimize your losses and assure you that the position is heavily weakened incase a second attack is needed.
I'll list some opennigs that will always criple ECA:
RussiaThe easiest matchup for them. You have so many ways to make ECA live in hell. For one, pick Recovery GP, it is probably the most overpowered ability in the game as it lets you revive your high stat units without any cost, and to keep the pressure up from the get go.
You can push any defensive position from tier 1. Mass conscripts from multiple barracks, a couple of kodiaks and tungaskas, an MTP will break most fortification-heavy positions. If ECA uses gun turrents to fend off your tanks, then build
Buratinos. Fun fact , they outrange gun turrets, ( if they derped, the use smokes, fire a full bairrage then go back, rinse and repeat). Really , use Buratinos with any tank force you build. They are better at breaking defensive lines that Gorgons ( Mstas ). Whenever you preform infantry tank attacks, use smokes 1 by 1 to outrun the defense line ( this is kinda broken since you can get ECA defenses stuck on a loop being distracted and forcing the other player to over-exert in micro which 9/10 he won't be able to do it due to the ridiculous demand in single clicks on the defenses to target enemy armies constantly)
2 Grumbles will deny ECA their entire airforce. If the game didnt end by then, spam sentinels, infantry, Mstas and secondary economy to end it.
You can always get topols to delete defense lines or preform economy harass. Or just go Goliath Hind/hellion spam.
Coilguns work very well too. All in all Russia has an eady time in this matchup.
ChinaChina is the second easiest faction to use vs ECA, they have very similar combined arms capabilities as Russia with the exception of the fact they can field tier 1 artillery. This means ECA have absolutely no counters to this besides either sacrificing expensive leopards, suiciding tigers or using harriers, which is easy to counter given the tools China has, like Mig interceptors and ECM Tanks)
Volunteers are defualt now, meaning having 5 of them will allow you to overrun most expansions ( since expansions usually only have 1-2 guardtowers). Mix them up with your battlemasters, galting tanks and whatever you want to be creative with.
You can also go for a dragon tank assualt. Bring 3 Dragon tanks, Firewall any defense line and I guarantee it's gonna melt unless it's overivested ( meaning that the flank is alot more open).
Really the only danger you are facing is the airforce, which can be countered by migs. Lets not forget about the fact you own 3 Very high area damage abilities , the Napalm bombings, the parabombs, and the nuclear missile. Use them to constantly take out ECa's economy and you've pretty much sealed the game.
USAUSA's matchuo for ECA had been made alot easier thanks to enforcers, who have the same damage as an upgraded inferno with blacknapalm preformig firestorms. However with USA you gotta abuse the fact that your factions is good on all fields of the battle ( while not being excellent in any). Mix up your stuff and always exploit ECA's weakness which is their overspecialized defenses and immobility ( though the Pandur/gepard rush currently breaks stuff for them, aside from Marakar I have not seen anyone consistently countering the rush). Abuse the fact that you have to force ECA to also spebd on stealth detection everywhere to avoid stealth comanche/Burton or nighthawks.
If ECA managed to fortify then you didn't abuse their defense weakness enough.
GLAThis can either be a very easy matchup, or one of the hardest ones vs ECA. Just like any other faction fighting GLA, you need to end the game quickly or gain the upperhand. If you dont manage to do that , then you're dead.
Conclusion :
All of this is based on 1v1. ECA is only a strong faction in the mid % highish skill levels, but any higher than that and they become a joke faction as their gameplay becomes very limited (Bunker , Bunker and more Bunker, what's a Leopard?). I suggest playing with ECA for a while as Xeres stated, so that you learn their numerous limitations, and then start owning other ECA plebs from there on out