I'm not suuure if proper nouns work, though sometimes they do. I do know he's summonable, in some way or another.
Well, the way the object creator works is that it lets you take parts from the system. You can't make something wholly new, but you could like, say, take Cthulhu parts, add clown make up and stuff, and change his programing with the simplified programing tools they provide to make Clownthulhu