[elmokki]

As the battles in Dominions are fought over land or under water I personally would find any sort of sailing ships mostly hillarious.

That actually just gave me a new nation idea though. Drowned sailors being reanimated by ancient evil. The actual drowned ones would be amphibians, but there'd also be a potential for huge masses of poor amphibian standard undead with more scimitars "newly drowned". A sunken magically moving ship would be cool as hell, but I don't really know if you can make it big enough and if I can actually draw a decent looking sprite for one.

For land castles they'd have "shoredrowned" poor amphibians to recruit too. Some of them might be better armored, ie knights and heavy infantry who have fallen to rivers in the middle of battles etc.