All ideas with Masterjun as a contributor

Add nets, on the basis that NetHack needs to have nets in it. You can throw them in pools to fish with, and throw them at small monsters to trap them in place. There could also be a trap that catches you in a net. You can also mess up throwing them and tangle yourself instead. Possibly, nets would be their own skill too.

For simplicity of implementation, they should create a temporary web on the player’s space (with a flag set so that it uses “net” in its messages instead of “web” and is probably harder/impossible to tear through at high Strength). Either nets would generate in stacks of 11-20 and get destroyed when the monster escaped the net, or they would drop themselves (most of the time) when the monster escaped the net and destroyed the trap. Either way, they should be fairly light.