Beyond the Sword changed many things about the game, and naval warfare was one of the most dramatically affected. The limits on aircraft units per city changed the scope, but not the basis of air warfare. The additional units in land warfare made siege units relevant again.
But war at sea was completely changed.
In the vanilla CIV4, naval supremacy was nice to have but not necessary. The worst that could happen from not owning the oceans was losing some fishing boats and an air strike here and there (which you could counter with land-based aircraft). After your massed stealth bombers whittle them down, a few battleships can take down entire fleets of weakened enemy ships.
Cruise missiles and tactical nukes changed all that.
Now, not having sea superiority means that large stretches of your interior can be devastated, and possibly even nuked. The AI also uses amphibious assaults more often, and in conjunction with missle/nuke strikes. At the same time, the equation for gaining sea power has gotten more complicated.
A whole new naval strategy is needed.
To start, let’s cover the main units.Missile Cruiser
This is going to be your main combatant. Once onboard missles are exhausted, this is just a battleship and should be used accordingly. Promotions should be for Drill 1, Drill 2, and then Barrage. The idea is that you want the MC to survive initial combat, and then start prepping the rest of the enemy fleet for destruction.
You shouldn’t feel the need to always have fully-loaded MC’s, but rather keep a few empties around so that they can fight the battles. Once the enemy is down to ~27 strength, a Drill 2 MC should be sent in.
In a protracted war at sea, expect to build (and lose) a lot of MC’s.Stealth Destroyer
This is a misunderstood unit in because it’s NOT a replacement for the destroyer the way a MC is a replacement for Battleship in every way. This is a brand new unit, like the Attack Submarine, and needs to be used in a brand new way.
Two basic role exists for Stealth Destroyers – surveillance and assassin.
In the surveillance role, the SD should have Flanking and Sentry to maximize the viewing radius. Surveillance SD’s (S-SD) should be deployed to make EVERY ocean square between you and your enemy visible. There can be no fog of war when it comes to naval warfare unless you want an entire fleet to sneak up on you. The specifics of how such a picket line should be ployed will be discussed later.
Another use for the S-SD’s is to sneak in and bombard enemy cities’ cultural defenses, if your picket lines are close enough.
In the assassin role, the SD should have only Drill promotions, and hold those promotions in reserve for healing injuries. Once you kill opposing SD’s, your highly damaged SD’s can be in the middle of the ocean but also be perfectly safe. That’s why your Assassin SD’s (A-SD) should be the vehicle of choice for finishing off damaged units or hunting down tranports/subs/carriers. They’re the only ones who can survive the aftermath.
SD’s should emphatically NOT be employed in a stack with other units, the way the AI does. It doesn’t buy you anything, since SD’s won’t defend against anything except another SD.Attack Submarine
This is a critical unit, because the AI really loves to use submarines to deliver tactical nukes. Once you have Stealth Destroyers, you’ll need Attack Subs in order to help locate and destroy enemy submarines.
Because Attack Subs should only be used against other subs or transports/carriers or heavily damaged units, it’s in the same category as a S-SD and should get Flanking and Sentry. Additional promotions should be Navigation 1 and 2.Submarine
This is also a crucial unit because it’s the way to deliver tactical nukes and additional cruise missles to a front-deployed fleet. There’s no combat role for the submarine because it’s not powerful enough to fight any of the late-game opponents head on.
If you want missle strikes – better to deliver it from a MC, which can follow up with an attack or survive a counter-attack after getting close to enemy shores.
If you want to detect/kill other subs, the Attack Sub is much better.
That’s why the main role of subs is to either shuttle cruise missles to re-load MC’s which have fired their on-board supply or to sneak in a tactical nuke. As such, submarines receive Flanking and Navigation 1/2. Beyond that, add Sentry to help avoid threats.Battleship
Whatever battleships you have as of the time that MC’s come along – leave them alone. There’s no need to spend money upgrading BB’s when they don’t gain any combat power and the supply of cruise missiles always tend to trail the number of MC’s on hand.
Instead, use the BB’s for the same role as they had in CIV4 original – escorting carriers and transports. Their MP’s are perfect, once the transport/carrier has been upgraded with Navigation 1. They’re just as powerful in defensive role as MC’s.
There’s no particular need to stock up on BB’s, and also no reason to change how you use them from the original CIV4. You can’t see SD’s or subs sneaking up on you, but that’s why you have surveillance SD’s and Attack Subs anyways.Destroyers
These are critical units which should be stockpiled in large numbers. Build them while you can and NEVER upgrade them. You can always build more SD’s, but the supply of destroyers you have are finite
DD’s have the ability to detect subs, they can move farther than the Attack Subs, and can kill the invading subs just as effectively. On top of that, they still retain their anti-air capabilities, so they’re not nearly as vulnerable to air assault as the submarines.
DD’s also come in the same 2 varieties as SD’s – surveillance or attack. Unlike SD’s, surveillance-type DD’s should be used to escort large fleets because it’ll provide some redundant sub-spotting (and killing) capability.
Otherwise, attack- and surveillance-DD’s should be deployed near shorelines because they’re so valuable and so vulnerable.Carriers
In theory, carriers are much less useful than before. Air recon can’t detect submarines or Stealth Destroyers, and the naval strike role which made Jet fighters valuable can now be taken over by missiles.
In reality, carriers are still useful for providing first-strike on detected submarines and MC’s which have been stripped of their escorts. More importantly, they have a HUGE role in one of the main purposes of the navy – supporting a beachhead.Forts
Technically not an unit, but so crucial it deserves its own mention. With BTS, fortifications act as cities for naval and air purposes. That means new tricks which were impossible before.
A naval unit can use a fort to create a land-bridge to cross an island while an enemy fleet must take the long way around. A ship can move from ocean-to-fort #1, then fort #1-to-city, then city-to-fort #2, and finally fort #2 to ocean. A crossing which might have used on the entire MP quota of a MC could instead be completed with only 4 MP’s.
A fort can also be constructed to give you secure naval bases in stretches of your territory where it makes no sense to plant a city.
A fort can be used to house fighters/bombers to help support your coastal defense.
Now, if you’re lucky enough to have an island off your shore, build a city on it just to be able to use it as forward air/naval station. Forts give you shortcuts to help chase down a faster enemy, and a secure way of bringing your transports further along before exposing them to attack.Naval deployments
There are several major categories of naval war strategy.
You can choose to fight a defensive action, where your fleets are deployed out of home ports and are tasked with killing any unit you see. The goal is to protect your own lands while the land war continues or you’re trying to prevent a landing.
There’s also the offensive approach, where you bring your fleets near the enemy cities to offer battle and to strike at their infrastructure. The goal is to decimate their coastal cities and wipe out their fleet.
Finally, there’s the sea-lane action where the goal is to maintain a secure travel route in order to ship in more units for the war in a distant location.
In reality, a large war will always involve at least some of each of the 3 in different phases. It might start with a defensive action, then you’d move to secure a sea lane to provide an invasion corridor, and finally shift over to a total offensive action.
Or it might be the other way around, where you deploy your fleet to a forward position to nail the initial stack-of-doom invasion fleet and then pull back to a defensive position shortly afterwards.
In all cases, there are some basic tactics to consider.Oceanic Surveillance
With the Stealth Destroyer, it’s critical that you cover the ocean with your own Surveillance-SD’s. Each S-SD can cover 14 ocean squares, so it doesn’t take that many units. Because enemy SD’s can easily move beyond the range of your S-SD in a single turn, you need to either deploy enough units to cover the ENTIRE ocean or establish two picket lines far enough apart that there’s no way that an enemy unit can get past your S-SD’s.
Between the S-SD pickets, you should seed in Attack Subs, also spaced out carefully to make sure there are no gaps. That’s the only way you’re going to spot the enemy subs given the disability of the S-SD’s.
In combination, the line should look like
S (enemy continent) N
–SD—-SD—-SD—-SD—-SD– (SD line 2)
AS—-AS—-AS—-AS—-AS– (AS line 2)
–SD—-SD—-SD—-SD—-SD– (SD line 1)
AS—-AS—-AS—-AS—-AS– (AS line 1)
S (home continent) N
(each + and - represents an empty ocean square)
The combined 9 spaces between the SD lines means that it’s impossible for enemy SD’s to slip by, and the double-line of attack subs also ensure that no submarine can make it past without being stuck in at least 1 location where your own Attack Submarine can see it. The absence of an Attack Sub is also a clue that there must be at least 1 enemy sub in the vicinity, so units in the 1st line should be prepared to move up to the next line at any time.
The goal is to NOT use the units in the line to make attacks and to place your own battle fleet in a position to attack only after detection of the enemy.Attack echelon
When attacking an enemy fleet, always check if there’s SD’s in the stack. If there is, send your own attack-configured Stealth Destroyers in first to engage them. Beyond that, use cruise missiles to soften up the enemy units to around 30 strength, and then send in your highest promoted MC which has Barrage. That MC will probably die, but naval warfare is about attrition – not experience. It’ll soften up the fleet for follow up attacks. Then send in additional MC’s until there are no units above strength ~20.
At this point, it’s time for the assassin SD’s to enter the fray and clean up. By holding back promotions, the same group of SD’s can be used to attack multiple fleets over time and they’re perfectly safe sitting in the middle of the ocean as long as you eliminate enemy SD’s.Forts and airpower
Airpower is less powerful now that nearly 1/2 of the modern AI navy can’t be detected by recon, but that’s why you deployed that Oceanic Surveillance network. Forts give you places to put Stealth Bombers where it can do the most good, and add to the numbers of deployed aircraft. Do NOT send in stealth bombers until the enemy jet fighters are eliminated, but they can be deadly against subs and missile cruisers.
Each fort should come standard with at least 1 A-SD and 1 S-DD, to provide full coastal surveillance. Then drop in a gunpowder unit with Medic to provide healing and cover against amphib assault.Carrier airpower
Given the danger of parking a carrier in the middle of the ocean, and how softening up the enemy fleet can be done via cruise missiles – there isn’t much of a role for carriers as before. Their job is now more specialized.
Carriers should also be based in forts/frontier port cities. They can sally out 4 squares, launch air strikes, and then retreat. Rather than trying to avoid the enemy fighters, you’re going AFTER them. Strike directly at the enemy carriers, and whittle down their fighters to open them up for stealth bomber strikes. That covers everything between line #1 and #2 on your surveillance net.
You can then reload with fighters from a secure home port during the same turn, and be ready to sally forth again.
In the assault role, carriers are a lifesaver. When an enemy city is taken, it’s never taken with the airport intact so the amount of airpower available is limited. There’s also no option to use nearby cities to provide extra air cover if this is the beachhead. Support the ocean crossing with carriers, and you can park as many fighters in the conquered city as you want. Then every available slot can be used for Stealth Bombers.Submarine shuttle
Unless you plan to use tactical nukes, regular submarines are mainly useful in finding other subs and bringing cruise missiles to bear. Like regular land units in transports, missiles can be transferred from subs to MC’s. That will help fleets to keep a full inventory of cruise missles without coming off their forward-deployed stations.
Since the surveillance pickets are keeping an eye open for any intruding units, the submarine carrying missiles to the front should have a secure journey, doubly so if the MC move back enough spaces to shorten the journey.Convoy Escort
When escorting convoys, you need a BIG fleet unless your sea superiority is so complete that the AI navy is completely decimated. But given production advantages, that’s unlikely. In general, a convoy’s escorting fleet units should reflect how many turns the fleet will be in transit.
MC’s = (# turns) x3
SD’s = (# turns) x2
DD’s = (# turns) x1
Carriers = 3 minimum
That’s a lot of ships but you should need 1 escort fleet per ocean and you can use it to escort 4 or 25 transports.
I consider the “typical” crossing to be 3 turns, landing the army on the 3rd turn. That means a fleet of 9 MC’s, 6 SD’s, 3 DD’s and 3 carriers.
At the start of the turn, move the carriers forward 2 spaces and send out 2 fighters to recon for large fleets. That will make sure you detect any large stacks of BB’s or MC’s for a detour if necessary. Next, send the DD’s on a roundabout route to the targeted rendevous point. With S-DD’s, you should be able to scan a 6-square wide corridor and still get the DD’s to the target point. Any detected subs will be struck by air power. SD’s with cruise missiles and subs with air strikes. Move your A-SD’s in for the kill and then have them rejoin the fleet.
As the final move of the turn, the rest of the fleet (MC, carrier, and transports) will move to the convoy station through a thoroughly sanitized area so that the AI won’t know for sure you have transports coming their way. Remember that the AI’s LOVE Espionage so they already know your port of embarkation. They just don’t know when the transports will sail. But they will know once your transports leave port, so it’s important to deny the AI precise location on your transports.
Final point – the transports should hold off-shore the planned insertion point as far as possible on the final move to keep out of range of land-based air and units which might sally forth from secure ports. That means even if you have the MP’s to gt within 4 squares of the coast on that turn, hold off 6-7 squares so that the transport can make a last-turn dash straight for the enemy coast.Coastline defense
With cruise missiles, stealth destroyers, and air strikes – defending off-shore platforms and fishing boats are just a quick way to get your units killed. Stockpile the work boats and leave those resources unguarded. A good surveillance network will protect your off-shre resources more surely than a bunch of sentry-duty MC’s or SD’s.Discuss this article on the forum