Underwater

Most custom maps have an underwater portion. This is an often-loathed part of the map, as it would be for landlubbers in-universe. The ocean is a stunning example of asymmetrical warfare; fish can't breathe on land, and horses aren't very good at deep-sea diving.

There are four types of underwater provinces. Seas are typical underwater provinces. Deep Seas are deeper, darker provinces, with far more consistent Temperatures. Kelp Forests are Seas with more vegetation, while Gorges are even deeper Deep Seas.

Maps generally have fewer underwater provinces than land ones, not even counting the caves. In addition, most factions cannot build underwater forts, though they can certainly try claiming them. Even underwater nations can't build Citadels (the fourth tier of forts) underwater, even in the Late Ages, though imps could make one in Three Red Seconds. The administrative powers of sea forts end at the coastline; likewise, that of land forts ends where the seas begin.

Humans can't breathe underwater, of course. Likewise, the Aquatic cannot breathe above-water, because they have gills instead of lungs. If someone somehow ends up where they cannot breathe, they immediately die.

The Amphibious bridge both sides of the divide. Most of them are slightly better at fighting underwater, but that's merely due to the conditions of underwater combat, which will be covered below.

Poor Amphibians can also bridge the divide, but they're decidedly worse underwater than on land. This is usually due to their bodies not being built for quick-and-easy underwater movement, or merely not being good-enough at the aquatic arts.

Water Breathing is a trait normally bestowed by commanders (for troops) or items (for commanders), that "upgrades" the bearer to a Poor Amphibian. For example, Pills of Water Breathing provide for 75 Size points worth of guys, including the commander holding them.

• There's also a similar Air Breathing trait, for Aquatics, but it doesn't have a shared version.

Underwater combat may seem odd for "landlubbers". For example, Bludgeoning and Slashing attacks suffer from significant drag, thus getting an Attack Skill penalty equal to their Length. Most aquatic troops use spears (which Pierce) for this reason.

Water is not kind to iron gear, causing it to rust and become brittle. This concern is abstracted out above-ground, even though rain might very well cause issues in real life; underwater, however, rusting can happen before your armies fight their first sea battle.

The environment is also un-conducive to a wide variety of magic spells. The most-affected path is Blood, since various forces (fluid dynamics, shark ghosts, et cetera) prevent Blood Slave sacrifices from having any effect. Then there's Fire, which is quite impeded by the inability to light a flame underwater, though it may still Boil and Incinerate foes. Air also has problems; aside from underwater fights not taking place in the open air, there's simply no way for a Thunder Strike to reach a target through millions of gallons of liquid.

• The path of Water gains quite a bit underwater, of course. Aside from Water Elementals doing their best in the sea, Water Mages can manipulate the fluids around them to blast, entrap, protect, and even speed up units.

Lastly, there are the stat penalties, or the benefits for those used to the environment:

Stat
	-1	-1	0	0	0
	-2	-2	-1	0	0
	-50%	-50%	0	0	0
	+1	+1	+1	-1	-1

Swimming does not let you enter the sea! It merely improves the prospects of Poor Amphibians and the Water Breathing underwater. Likewise, all traits that let you enter the sea also let you cross Rivers. This added functionality to the Swimming trait is new to Dominions 6.