Building customization

So i saw different styles of in game building like fortnite and so on but, there’s one that i want to use but no one seems to use it or think of it. It’s basically the most creative style of building, you place the rocks one by one on top of each other or however and wherever you want them. Now i cant seem to do that in UE4 so can someone help me out? Thanks

Not too much detail here to go on. See if this can get you started:

Image from Gyazo

Disclaimer: there are no features here, also utterly untested; but since there are no features, it should work as is. The aBlock is an actor with a static mesh.