How to beat aliens

1. Your ank/artillery tech lvl. are crucial. The main reason aliens are so strong is their high shield. You need to get over +50 shield penetration to produce unhindered output.

2. Artillery is the most effective force against the aliens. They have skills that increase attack by large % against infantry and armored units, but there is no single skill in the game that gives buff against artillery.

Yet this is not to be applied to all circumstances. In conquest rocket mass rocket artillery spamming is the way to go, but in campaign you have little time and resource for them to be effective, so you'll have to fight with what you've got and probably spend most resources on nukes and missiles.

3. Skills:
Plain fighting: +20 when on plain.
Tide of Iron/Artillery Barrage: +24 when below 50% health.
Explosives: this gives +32 against alien towers. Of course cities too.
Supply/Ace forces: a surviving skill is always helpful
Street fighting: can be extremely useful in defensive situation when used in conjunction with plain fighting = +40
Blitkrieg: life saving skill for tanks


4. Generals.
In alien missions, ideally you'll want to have the following lineup ready:

Conquest:
a) 2 tanks / 4 artillery (easy starting position)
b) 3 tanks / 3 artillery (tough starting position)

Your main force will be unstopping lines of RAs, but you also need 2~3 tank generals to wipe out the initial line of enemies, steal their cities and boost income ASAP. That's the sole role of tank generals; once your RA forces are rolling, you've got all you need.

Campaign:
1 infantry / 3 tanks / 3 artilleries / 1 air
Campaign gives you little choice in your army composition, so you need to have a flexible selection of generals.

They build in anything, we don't know how much it costs 'em

Aliens are the hardest ones