Ah, I think I found it. The repeater would be the only logical explanation on achieving this effect?
I wouldn't simplify it that grocely. As they say: There's a million ways to skin a cat. the specific implementation very much depends on what look you have in mind. Yes, using a shape layer repeater is one option, but it is limited to shape layers and does not randomize colors for instance. Therefore, you will have to look into otehr methods as well. One of them could be this script, otehrs could be conmbinations of effects like Card Dance or Particle systems and using their ability to distribute items randomly. So I recommend you do a more extensive generic search on the matter of "repeater", "trails", "echo" and "layer stacks" andplay around a little. If you come up with specific design we will be glad to advise. Otehrwise there is not much point trying to cover a topic in a single forum post that could fill an entire book...
Excellent! thank you very much as I was experimenting with the repeater and will look closely into the others