Board Thread:Off Topic/@comment-24993958-20151118083252/@comment-25857155-20151206020646

...Might I suggest a better idea? Allow the user to partially shapeshift part of their body into that of an enemy or other form.

Any semblance related to Grimm is pretty much automatically rejected, since Grimm have no Aura and Semblance is a manifestation of Aura - unless it is something like summoning something in the form of a Grimm. Nothin' that turns you into a Grimm will be accepted, even if it's only partial.