MOTHRA larva

I don't know what this thing is but it crawled under the door of my studio and it was kind of cool but I think it wanted to eat me. I calmly removed it to the other side of the patio and it CAME BACK and crawled in under the door AGAIN!! then I had to drop it onto the neighbors roof. Please notice my hand next to the monster, for scale. Can anyone tell me what this thing is going to be when it grows up?