I've seen a lot of Paragon Paths themed around storms and around ice or cold, but not much to do with (liquid) water. Sea Tyrant's Oracle seems to have the most, and that's just the fluff and the daily attack power. The same pattern seems to follow for the powers.
Anything notewothy I've missed?
Okay, I'll edit in a running list of options listed on this thread:
Subclasses
- Water Elementalist Sorcerer (HotEC)
- Eternal Tide Monk (HotEC)
Prestige Classes
The Rain Bringer has been listed, and cited to a book I don't have (DSCSB). Otherwise:
- Sea Tyrant's Oracle (P-AP)
- Elemental Savant (HotEC)
- Astral Savant (P-DP)
- Sword Coast Corsair (FRPG)
Feats
- The Thaliessen Blood feat (Dr Mag 401, half-elf only)
- Born of the Elements (HotEC)
- Child of the Sea (HotEC)
- Seastrider (HotEC)
Other Options
- The Watershaper theme (HotEC)
- Mariner theme (Dr Mag 412)