Here’s a little intro video that shows how to chain together some ICE Modeling nodes to build extrusions on top of extrusions.
See Extrude and extrude and extrude… on si-community.
Here’s a simple example that extrudes the polygons in a grid, and then applies a second extrude op to the extruded polygons.
I modified the Disconnect compound to output the Topo, just to make it easter to connect things. Really, I should probably daisy-chain everything in this example.
Chris_TC did something more sophisticated here.