With 10 minutes of work, the nharyth can create a web of nearly transparent spines in a 20-foot cube. The web must be anchored between two solid masses or layered across a floor, wall, or ceiling. A web of spines layered over a flat surface has a depth of 5 feet. The web is difficult terrain, and the spines forming it are nearly transparent, requiring a successful DC 20 Wisdom (Perception) check to notice them.

A creature that starts its turn in the web of spines or that enters the web during its turn must succeed on a DC 16 Dexterity saving throw or 1d4 spines stick to it. At the start of each of its turns, the creature takes 1d4 piercing damage for each spine stuck to it. A creature, including the target, can take its action to remove 1d4 spines. If a creature starts its turn with more than 4 spines stuck to it, the creature must succeed on a DC 16 Constitution saving throw or be paralyzed for 1 minute. The paralyzed creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

The nharyth can plant up to 24 spines in a web when creating it. Once it has used 24 spines in webs, it must finish a long rest before it can use this trait again.