I’ve been leveling up my main in Nagrand lately and I came across a decent spot to farm for Motes of Water. I’m sure there are other, even better, locations to do this but I had a lot of success in this particular spot so I thought I’d write a post about it.
My “secret spot” is the large lake northeast of Garadar and immediately south of the Throne of the Elements. Here’s a map to make things clearer:

I was getting Motes of Water from the elementals at a pretty good clip. It helps if you have something that will give you water breathing though.
