majikk
My solution works perfectly well if you choose to create an object instead of spawning it.
With System create object, there is no need to have an instance on the layout.
With spawning there is no need to have an instance either. You just have to make sure the object that is doing the spawning is on the layout. So only if this happens to be another instance of the object is it necessary to have that instance on the layout, but because you were talking about a catapult, I would expect the spawning to happen there.