the only thing which would concern me is the unristricted invisiblity. With a power like that I feel this would have to remain an NPC.
No kidding? ;)

Thats why I gave it no LA. No way should it be a player character.


would/could the stream have a relationship with aquatic creatures? as an example, could a bunch of aquatic heros team up with a stream to adventure on land by "breathing" from the stream?
Ermmmm... possibly, mechanics wise. Its not really, strictly speaking, water. Probably need to elaborate on that in the text.

Then there is the fact these things don't think highly of mortals. If you had a group made up of Uldras (only Fey I know of specifically made for player characters) though that'd might work.