Based on the Net Koopa dissasembly by imamelia, this Dry Bones acts like a Net Koopa; however, jumping on him will make him crumble and act like a normal Dry Bones. The generated Dry Bones will stay behind nets if the Net Dry Bones is jumped on behind the net. This sprite requires a patch that is included in the .zip.
Tested with: LM 3.10, pixi 1.2.12, asar 1.71, SA-1 1.32, Snes9x 1.60.
The sprite works fine, besides a small issue that you could look into for an update: when stomping it behind a net, the spawned dry bone will be considered "behind the scenes" even if he walks away from the net, disabling all interactions with Mario even if it looks like they should interact (unless Mario is behind the net himself, of course).