I was thinking that the Wesens are all afraid of Grimms because if Nick is any kind of example they do kill a lot of Wesens in a short period of time in a relatively small geographic area. This is what I came up with off the top of my head and I wasn't sure if I was missing any:
Three Reapers
One Dämonfeuer
At least on Geier
One Mellifer
One Schakel
That's all I can think of so far.