This is the setup to create a collection with your new symbols in the Symbol Manager when you hit the Options button.

Ok - varicolour eggs ;)

Well, maybe the eggs I've done can be dragon eggs?

I imported them at 200 px per map unit, so you can make them larger if you want, but I think they might be a bit obvious at full size if you are trying to hide them among the fragments. Full size would be if you want them to be noticed straight away.

Do you mean something a bit like this, @jslayton? Something where you don't actually know for sure what it was that just hatched out?