How to copy object to new levels sequentially?

Hi all,
I’m trying to copy some object to new level and delete them in old level then save as it as a new file. And do sequentially for the next level. But i get a stuck in red area, i want to make a ‘loop for’ to the value appear sequentially but i can’t find a node to do that. Can someone help me? Thanks in advance.

I think you will need to have some test to make them sequential. For instance, sort / arrange them by elevation to make it start at the bottom or top depending on your needs.