R_N
Well-Known Member
It's hiding in a regular grass patch and will pop out when you enter that patch. The shaking patches has nothing to do with the Shroomish of the mission really. Your walking pace is also irrelevant to the encounter. You can't locate it beforehand as far as I know and the best way is just to walk through all the grass until you find it.
Huh, so it is
I guess it was just coincidence last time that I walked up to a poochyena while a pokemon was rustling