Board Thread:Speculation House/@comment-14138255-20151129182644/@comment-25396609-20151129184847

24.93.195.246 wrote:

The summoning Grimm, people are gonna go all sorts of directions with this Here's a thought, they're not actually grimm.

"Now think to your fallen foes! The ones who forced you to push past where you were, and become who you are now. Think of them, and watch as they come to your side."

They are a manifestation of the emotions they experienced while fighting a specific foe, and they take the form of that creature. Not a grimm, it just looked like one.