Problem using Multires sculpting! I am trying to Sculpt a character using multires and i tried to shape general forms in lower Sub and move on to higher subdivisions step by step but after forming the basic shape that I wanted subdividing cause this artifact!





Notes:

-Rot scale applied

-Base mesh did not changed in edit mode

-apply base makes it worse  

Does anyone have any ideas?

Thanks for your time!
The problem was modifying overall shapes of a pre defined basemesh using "grab" brush.

changes in major shapes of a basemesh using grab brush creates artifact using multires 
subdivision