Take the tour ×  Very rarely do I see the rustling grass when
I'm walking through it. What are the determining factors when
the grass starts to shake? Is it just a random event? Is there
any items or a pokemon move that I can use that will increase
the chance of this happening?  share|improve this question add
comment  1 Answer  up vote 3 down vote accepted  There does not
appear to be any way to increase the chance of rustling grass,
or the water/cave equivalents rippling water and dust cloud.
They seem to occur after an unknown number of steps have been
walked, and they only seem to appear on the current screen when
this number of steps has occurred. So for best results outdoors
find an easily accessible patch of grass near a grassless path,
and then walk back and forth until grass rustles. Same idea for
water ripples. Try not to pace in an area where both water and
grass can be seen, as you may get a water ripple when looking
for rustling grass.  Ideally you should use a repel when heading
into the grass/w