The three full sets. Renee (WePamperPets) had suggested I put the ramp covers upside-down, and it worked REALLY well, but Tootsie ripped a red cover in half, so no more. (You can tell the more recent picture is the pink camo because of the ramps. ) They're always numbered in the order I got them.
You can also watch the evolution of the feeding den. Feel free to copy the idea, although I'd suggest using something like shoelaces that are stronger than clips.