Why limit yourself to only one? My next campaign is going to be Eberron+Pirates.
Who said anything about water?Rather not have warforged and Artificer's in a naval game. Warforged don't breathe and I don't really want to mix magitech with sailboats.
Who said anything about water?
Sky pirates FTW!
You could certainly play something similar.
Who said anything about water?
Sky pirates FTW!
(and it's really quite easy to come up with characters who don't need to breathe or can hold their breath for an extended period. It's much the same as flying - I wouldn't design a 5e encounter on the assumption that the PCs can't fly, and I wouldn't build an encounter on the assumption that everyone has to breathe).