Need the name of a third party book

[Nightstorm]

I know I had it as a book and pdf and now I cannot find either.
It was a 3.0 or 3.5 Monster book
It had a Fey touched Template
The example used was a horse. I need that template and now cannot remember which book it's in.

 

[krupintupple]

at first glance, i wanna say Fiend Folio...but my books are currently in Ottawa; I am not, so I cannot check

 

[GreyVulpine]

Hmm, the one in Fiend Folio had an example of a half-fey template, with a half-fey centaur as an example. Was this what you were looking for?