Gunboat: This is the cheapest boat you can get. Don't
expect it to do much against other ships, but it's specially
effective when guarding missile boats due to its good AA
Destroyer: A terrific ship, always try to make the
Destroyer your main naval unit. Double medium cannons and
a couple mortars assure you not only a great navy for sea
based fights but also a great artillery and support unit
able to bombard structures and units right from where the
enemy least expect it.
Cruiser: Don't count that much on the cruiser for
AA, with its long reload it's not as good as it first seems.
Where the cruiser really excels at is detecting enemy spies
on its radar range and deploying sea mines, which basically
define limits to your naval domains.
Missile Boat: The best artillery unit in Z:SS is
a ship, and it's called "missile boat". Never
go straight for them, though, 'coz missile boats are paper-thin.
Try to get a good amount of gunboats and at least a couple
destroyers guarding it. Once you have it, it's easy to start
spreading terror (and an anti-missile urgency) on your opponent(s).
Try to use spies or suicide scout choppers to give it LOS,
there's a good guide to this technique at the FAQ section.
Remember that once the missile gets over its target it'll
detonate and scatter many bomblets, forming an "attack
umbrella". So, if you want to hit one specific target
it's better aiming at something slightly northwest or southeast
Battle Cruiser: A frightening war ship, the Battle
Cruiser has the power to destroy many enemy boats before
going under, due to its heavy cannons. Following the Z:SS
phylosophy of attack-powered units being not that resistant,
don't expect a super-resistant armour on this one. So you'd
better give the Battle Cruiser some good AA and naval cover
in the form of gunboats and destroyers.
For more useful info, read our Z:SS