I've spent quite a while doing achievements and it was usually all against many hard AI players. I saw no quality guide on AI yet, so I thought some people could use one. It's for medium and big maps where you have time for at least 6 planets before you have to fight a war. Smaller ones are boring and i don't play them. Find a different guide telling you how to spam LRMs on those and you're all set.
Anyway, here it goes:
1. Knowing your enemy.
Try to remember against whom you're playing. Play all the races, get to know them. You need to know which AI ships are carriers, which have repair ability, which hit hard and which are most durable. Without knowing races and their ships, you've already lost. So do learn.
Scout ahead and see what planets they have, where they are, how hard they are defended, how many and what type of ships they have. It's funny how people neglect such basic stuff. With this knowledge, your offensive will be very easy. So go and scout.
Knowing their personality helps a lot too. The worst guy is called defensive. He expands slowly and keeps fortifying his interior planets. Do not waste time playing against this guy. The best AI (the most annoying one!) is aggressive. Researcher will have little but elite ships. Piece a cake. Cash guy will have loads of light frigates. Pick your favourite. Or go random, it's somehow more fun this way.
2. Building up.
This is a long one. But you have to DO IT RIGHT in order to get advantage over numerous AI players. If you don't, you're dead.
Start the game. Buy 200 crystal as fast as you can.
You have a green planet at the beginning. The first thing you do, you should upgrade taxes on it. AI won't do it and it means you have 40% more income for first 10 minutes. It helps.
Second thing, build cap ship factory and crystal extractor. Queue the capital ship with colonization ability. This is your second early advantage over dumb AI which 90% of time takes some other ship.
You need to know one thing. Colony frigates are damn slow at colonizing planets. Jumping burns their antimatter and they need to regenerate it for like 10 minutes. If you don't take a colonizing cap ship, your colonization will be damn slow. Trust me. Do not waste this early advantage for a Kol.
Next step, build scout frigates. I build as many as I have phase lanes from my home planet but never less than two. I send them in all directions and when they are on their way, tell them to autoexplore.
When the cap ship is ready, create a fleet out of it, build a squadron of fighters, tell it to jump with all the fleet, set the formation to close and jump to a nearby asteroid. There's always an asteroid.
When you're there, you will see two frigates. Kill the one that can bomb planets, the siege one. Your fighters excel in that. They make up for you not having a fancy battleship. They really do. When siege frigate is down, colonize the asteroid right away. Second frigate can be killed after you have the asteroid, saves like 2 minutes of time.
Build taxes, build mines. You've doubled your resource income.
2. Looking around.
By now you should have most of nearby planets explored. Build two civilian labs. You need to invent ice or volcanic colonization for your next planet. There's always an ice or volcanic planet nearby. Always.
After labs, build 5 to 10 light frigates and send them with your colony cap ship to take the planet. Send cap ship first, let them gather around it and start shooting at it. After that send in your frigates. This way they pound you capship's huge shield while your frigates stay safe. You save a lot of cash due to this trick so do use it. This is your third huge advantage over reckless and losing dozens of ships AI.
3. Colonization.
At this stage you should start thinking about having like 5-6 planets all with trade ports. This is one more thing AI fails to learn. The one who goes for trade earlier is the one who can muster bigger fleets in mid-game. AI doesn't do that and is sad and poor for a longer while.
Also you should invent better shields and your long range frigate. I like TEC one even despite overusing it is very lame. You should also get your second capital ship, this time it should be the best and toughest bitch you have in your fleet. I mean Radiance, Kortul or Kol. Two caps with a bunch of long range frigates in this stage is all you need.
Last thing to do, find your first victim.
4. Choke points, it's all about choke points.
See what route this AI will have to take to reach you. You need a point AI has to fly through to reach your home planets. When you find it, colonize it. It has to be close to that AI. If the map is sane and you're fast, it should be no more than 3 jumps from his home planet.
Build two repair bays there. They should overlap so they heal each other. Also build a crapload (3 to 5 at this stage) turrets. I know they have low damage and their range sucks. You don't use them to fight back. You use them to delay or scare away the AI.
Spread them and try to cover the whole half of the gravity well to which AI will be jumping.
And DO upgrade escape facilities on that planet/asteroid.
Of course research repair bay first. Research hangars to. Build one or two if you have enough cash, all fighters.
4. First victim. Coward.
Why did we secure that planet? Simple. When you attack AI, it jumps to the system you came from with siege frigates. If there are no defenses, they kill the planet and go further into your territory forcing your fleet to turn around and chase them. Now when they see you built a crapload of turrets, they turn around (80% of time) and fly away. If they don't, you should hope your turrets will hurt them.
This strategy is cheap but for a newbie player is deadly and extremely annoying. So plan ahead.
Do not turn back your main fleet. Start bombing his planet as fast as you can. Leave buildings and minor fleets to your frigates. If he has capital ships and doesn't run on seeing you, target them first with all you have. You kill his cap ship and he runs away. He runs away and the planet is yours. So instead of pounding frigates, kill his cap ship and you've won the day.
Proceed with this strategy until you have wiped him out.
5. What we have so far.
We have invented basic defenses, we have i don't know how many but a decent number of planets, at least two of them being terran ones. They are the ones that give real cash. Two or three cap ships. Better shields. A bunch of frigates.
6. Fortification.
Secure your borders. Every border planet should have max escape facilities, two repair bays, a hangar or two and a bunch of turrets. Move your capital to be somewhere in the middle of something you consider your future territory.
Move your firgate and cap ship factory there. Scuttle those on your home planet and build trade ports there instead. Invent and start spreading culture. Start thinking about resources inventions too.
Mass your ships together, add 3 or 4 new capital ships. I usually build one of each type and after that mass what I like. For Vasari I have 1/2 Kortul, 1/2 Sikantra, for TEC 1/2 Kol, 1/2 Sova Carrier, for Advent I usually go full carrier.
7. Mid-game offensives.
Here you have to remember that AI is a coward. It will run away if it's not his last decent planet and if it sees you have more cap ships and advantage in fighters and bombers. Use it. Do not spread you capital ships
Also, colonize and fortify each planet you take. Proceed slowly but in the fashion that ensures your rule over this planet for a while. Two repair bays, two or three hangars, a bunch of turrets and it's considered secured.
During battle, leave your cap ships on the wild but focus all frigate fire on his cap ships. Start with weaker, support ones. Dunov is my favourite first target. So is Advent mothership. They are soft but have powerful abilities you want them to stop using. So kill them first. And remember, AI will eventually run away even with a big fleet. It's just scared of capital ships of yours.
Invent max shields, improve your weapons too. Mass cheap frigates, especially light and long range ones. Quickly go towards 16 cap ships in your main conquering fleet.
Never think "i'll sit back and turtle for a while". Always stay on the offensive, always keep your fleet busy. You are safe when you're moving forward and reducing htem in size. WHen you let them to mass their fleets and come to you, you are dead. If they hit a planet far away, just build frigates and send them there.
8. Bombers.
For your main fighting fleet you need 40-60 bomber squadrons. I don't care how you do it. Can use capital ship carriers. Can use your little carriers too.
When a battle starts, alt+click them to get them all under your command and use ALL of them to hit one cap ship of teh enemy at the time. Start with soft ones, you should know which ones those are by now. This amount of bombers kills cap ships in one or two hits. Without cap ships, they run away 90% of time. So hit them with that much of bombers and the battle is over in half a minute. Of course stay sane and add some fighters to that fleet and some long range frigates too.
9. Late game offensive.
Now it's wild. You know what to do already, just use twice more ships for that. Have fun. Research everything.
10. Pirates.
Don't kill them in their base. Never. They are too useful. Keep sending them on AI that seems to be the strongest. And do not let others send them on you. Even if you can beat pirate fleet, it's better to have AI spend time and ships on it instead of you having to fight them for ten minutes.
11. Saving cash.
Do not explore your planets. Waste of cash. 90% of time you find nothing, 5% it's something useful a tiny bit, 5% it's something useless or a penalty. Most of artifacts are crap anyway and finding the one or two you consider useful is almost impossible. So do not explore planets, colonize more of them instead.
Do not build rafineries until late mid-game.
Do not build culture until you start bordering AI culture.
Do not invent faster mining until you have 6-10 planets.
Do not invent anything that raises bounty, waste of cash.
Do not invent culture spread bonuses.
Do not build propaganda everwhere. Build one for each two jumps, it will be enough.
Do not build defense on your inner planets, AI never jumps inside your territory anyway. It settles for border planets so keep those secured and you're fine.
Do not invent bigger fleet capacity until you really need it (ranked 10th in fleet is that moment).
Do not build super weapons. They cost too much and are worthless 90% of time.
12. NEW: Planet Defenses.
AI doesn't know anything about how to build them to maximize their use. Even defensive AI can't get it right.
It's one very useful area in which you can make up for their numerical advantage. Provided you know a few basic rules. Here they go.
The rule is that defenses aren't to kill the enemy. Maybe if turrets had bigger range and had some sort of anti-aircraft defense on them. But they don't. So most of the time your defenses aren't there to actually kill what jumps into the system. They are to scare it away. To deter AI from attacking. When you have decent defenses, it often happens that AI jumps in even with a substantial fleet but resigns from the fight and jumps out right away. So do build defenses, do not rely only on ships.
Enough theory. Now practical stuff.
First of all, repair bays are the best defense you might have. They are better than anything else you can build there. Always have two or three of them, preferably overlapping each other so they can heal themselves while enemy starts pounding at one of them.
Second, you need hangars. Preferably in the area where they can be healed by your repair bays. Hangars can produce two types of aircraft. Bombers are better for late game when enemy comes with more capital ships and cruisers.
For early game you should go full fighter. This is because fighters are deadly to siege frigates. And siege frigates are what you want to kill quickly as they kill your population and destroy your planet. I noticed AI is very unlikely to bombard with capital ships. So your planet stays safe after you destroy all siege frigates. So killing frigates should be your priority.
I build two or three hangars on my planets, sometimes go for four on planets that are choke points. Helps in hunting scout frigates and other travellers.
Rule three, build lots of turrets. They all have 3000 life, have decent armor and shoot back. Along with repair bays, they can survive a lot of pounding and slow down even huge fleets. Place them somewhere in the middle between both yellow circles around your planet to cover the half of the hemisphere where the enemy will jump in. In systems endangered by pirates, build one or two near your trade port and mines. You need many of those cause killing them takes a lot of time and you need time to bring reinforcements.
Four, culture. All civilizations get some bonuses in their own culture so make sure that border planets are influenced with your culture. TEC gets only antimatter regen bonus so is somewhat weak here. But Advent gets better shield mitigation bonus, making their ships twice more durable. Vasari are the best, 13% more damage in their culture. So culture hepls. Of course each of those needs research. Do it somewhere in mid-midgame before AI comes with some serious fleets.
Five, defensive fleets. For those I build lots of long range frigates (like LRM, Illuminator) and heavy cruisers (like Kodiaks). Kodiaks or other heavy cruisers come close to the enemy and thus take all the beating while long range frigates keep shooting from behind cruiser line dealing lots of damage and remaining safe. This fleet also should get one most supportive capital ship you have in your fleet. Preferably Dunov/Mothership type. The one that regens shields or repairs. For Advent I spare one carrier with repair cloud. It needs to be a support ship cause... it will be doing support.
I station this fleet where I think AI will hit me and move it around to where I'm hit. It usually happens to have enough time to get there before everybody is dead due to many turrets i build delaying enemy's offensive.
I don't have a huge defensive fleet. This is possible because I keep producing new ships and sending them to where the fight is.
Phase inhibitors, I build those in choke points to stop enemy from scouting. Along with additional hangars. Other special buildings I don't really do much, and usually late in the game. I quite prefer to build more turrets. I also don't do superweapons, they are costy and not that useful.
Last thing, scout ahead and check what capital ships are going to attack you. It is is very important. You need to know if they have many carriers. If they do, you need flak frigates or you're dead. So check this thing out.
END of update
Take care. Comment oin the guide. I'm open to suggestions. I will be updating it.
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