Go to Sunken City. Go to the gate (don't go in) and go to the left. Go straight back and there is some behind a rock. You may have to go several times, because it is a rare find.
best of luck getting what you need. with all the young mages running around wizard city. picking up regents for fast gold. its super hard to come by blood moss. you can camp at the bazzar and hope someone sells some. but then you need to be quick to by it. because others are camping there for it to. this needs to be fix, maybe by putting some in another relm.
There are a few plants to be found on Grizzleheim in the Savarstaad Pass, but not a lot. I was hoping to find some in the other areas of Grizzleheim, but so far no luck. More stone blocks, ore and frost flowers - boo hoo.....
