This guide isn't intended as a step-by-step walkthrough, and I certainly don't think that my approach is the only way to skin this particular grox, but if you've had to restart a couple of times this might be of use to you.

Bear in mind that I'm going to be laying down broad doctrine, and you'll find situations where the tips I've given you are not the correct way forward, so temper this with your strategic situation and common sense.

This section is more of an explanation of the overall concept that informs the shape of the lower stratum.

Essentially, your war aims are to enter each stage of the campaign with the highest development levels, renown score, and fleet strength that you can. My impression is that each story mission contains the same number and strength of foes no matter when you approach it, so it makes sense to spend time making sure you've got the biggest, baddest fleet you can get when you go into them. It's the same concept as making sure you do all the side-quests in an RPG before pushing the story forwards.


Please forgive the capital-ship based pun

The secondary string to this is that you don't want to have to spread your fleet about if you can at all help it. This means that completely conquering a sector is of high importance.

I've found the campaign to have two gears. When you first access a sector, it pays to be highly aggressive, ideally capturing the entire sector before the Threat levels and Urgency increase too much. Of critical importance, is that you hold off performing missions that advance the plot for as long as you can, as each one of these you accomplish resets the Urgency track. In the very very early game, temper this advice a little, as you have to take a little more balanced approach to begin with.

In the aggressive phase:

• Don't forget that you can bypass enemy systems and attack targets behind enemy lines. Always go for the weakest targets you can.
  
• Grabbing systems earlier means they can spend more time levelling up, meaning that they give you the best benefits soonest
  
• Don't build minefields unless you absolutely have to, in response to a specific attack, this is because:
  
• Enemy attacks [Not Invasions] are actually very good for you, especially in the early game where the cap on your fleet strength means that an enemy minefield can put you at a very serious disadvantage. I've lost count of the number of times I've been able to capture a system because the enemy have split their force.
  
• On the subject of the fleet size cap, this limitation makes enemy fortifications bad news for you, which is another reason why resisting the urge to hesitate is of paramount importance.
  
• Securing more systems gives you buffs and reduces Threat at certain thresholds. This is important because these small buffs can make a big difference in combat, and the threat reduction means that if you're forced to go into the Passive Phase before you've completely conquered a sector (usually when you're left with one very heavilly defended system you can't crack at your current fleet limit or tech level) you don't have to worry so much about enemy action disrupting your plans, or forcing you to go into the priority mission with a damaged ship or two.

The quicker you can secure the sector, the better, because it gives you more time in the passive phase. This is where you sit back and soak up turn after turn of resource generation and evolution levelling, and the best point to start levelling up your planets. I'm not suggesting you wait until you're a couple of turns away from losing the game to go after the priority target, but the more time you can spend here, the better.

As a broad rule, this is the order I upgrade planets. This assumes a strong income stream (at least enough for a level two upgrade per turn) and so once again you need to be more balanced in the very early game. Given the amount of time it takes to go from level two to level three, level two upgrades should be considered one tier higher on the list below.

• Agriworlds first. Individually, the bonus isn't worth much, but if you're planning on upgrading everything in a sector (and you should be) then going for the one that makes that cheaper makes sense. If you do the maths, it takes a lot of level-ups for Agri-Worlds to pay themselves back, HOWEVER, that doesn't take into account the time Agri-Worlds can save you, nor the extra turns of resources from other features that you can access early.
  
• Features that give you Renown. Having more tech, more upgrades and more fleets makes everything easier. If you take a short-term view you can end up neglecting these features and being underlevelled a bit. There aren't that many of these so you're not losing out that much by getting them out of the way early. Also it may not feel like it at the start, but your main limiting factor once you gain access to 3-5 sectors is not going to be income, it's going to be the size and number of your fleets.
  
• Resource generating worlds, with higher-value ones taking priority. This is perhaps the only class where a level three upgrade is more important than a level two, given that the bonuses double with each level. If your income isn't very strong yet, or weaker due to fleet upkeep, these take more priority.
  
• Features that make the system easier to hold, such as reducing threat, increase attack timers, or the Archeo Gellar Field in the Obsidian Depths.
  
• Features that give broad buffs to your ships - these tend to be small buffs, but are more valuable than ones specific to ships built in that sector.
  
• Any shipyards you didn't upgrade for quicker repairs during the aggressive phase
  
• Any features that only benefit ships built in that sector.

As for Fleet Composition, I tend to make my Navy fleets "top heavy" compared to the other factions, partly because the Marines and Admech don't get access to Battle and Grand cruisers and have compelling reasons to use swarm fleets of smaller-tonnage ships. Therefore, I use Navy fleets as my main combatants, with the other factions in support.

My Admech fleets are pretty much uniform - as many Dictators as I can stuff into the fleet. Because it's an Admech cruiser, they come with dorsal lances and nova cannons as standard. This allows me to focus on direct-combat ships in my IN fleets, and torpedo-armed ships to make best use of the Short-Burn torpedoes that ships in Spire's fleet get.

I use my Space Marine fleets mostly for boarding, especially as "giant killers" - it's more economical to use boarding to kill a Space Station or Battle Cruiser, for example, than try and batter it to death with weapons fire. Especially, if like me, you engage the defending fleet away from the station and have used your strike craft and torpedoes etc on said fleet.

Early game, escorts are excellent. They hold up a lot better versus the smaller fleet sizes, they're great at capturing strategic points, and are great scouts. Early game, you can set them on pesky Chaos escorts and leave them to it, hounding them and preventing them from sniping from stealth while you concentrate on the main battle.

I have found, however, that they don't scale that well later in the campaign. You normally have enough firepower to blast the enemy out of the sky at that point, and capturing the points is less important. Also, you're facing more enemy ships, and having to repeatedly replace escorts is inefficient. The possible exception to this are space marine escort ships, because they can perform the strong "Honour the Chapter" assault action, and the more ships you have the better when it comes to boarding strategies. I also favour the SM ship variants with launch bays like the Strike Cruiser Mk.1, over the ones with torpedoes or lances, for tactical flexibility.

A note on upgrades: I personally favour the Hull and Shield upgrades for extra tankiness - but my number one pick is the Armour-Piercing ammo upgrade.

I'll preface this by saying that normally if you need a fleet then and there, it's better to pick a sub-optimal admiral rather than hold off until a more favourable leader rotates in. Therefore, if you want to follow my recommendations, you should use it more to decide which of the two options you're going to pick. I'll just put all three factions together because there is a lot of overlap between the skills.

Bottom-tier

Augur Disruption Bomb - Basically has a *very* narrow window of use just before battle is joined, but the AI escorts will just Mark you anyway.

Mid-tier (lower division)

Mid-tier (upper division)

Top-tier

This is just going to be a random grab-bag of tips, rather than anything too coherent.

• Keep your ships alive. The higher level experience bonuses are rather strong, and make the investment you've put into your ships give you that much more return on your cash.
  
• Vesus Chaos and Eldar, focus their engines and use boarding liberally.
  
• Against Eldar, always advance. If you take the pressure off of them, they'll stealth up and blast chunks out of your ships. You're aiming to pin them into a corner of the map and slaughter them with close-range macro-cannon fire. Your AOE/skillshot attacks are very effective against them, as they bypass Holofields - however, the Eldar also find it easy to dodge them. Use your skillshots to herd them towards you, rather than trying to do pure damage with them.
  
• If you get a Domination battle, and you've got a firepower advantage, go for an annihilation victory. If you're at a disadvantage - especially if you have defence platforms etc to give you an early cap advantage - then go for a capture victory.
  
• When combat is first joined, pause and make sure you have Stances assigned to all of your ships. Even if you don't make an optimal choice, any buff is better than none.