Net trap
The net trap is a trap which drops a single throwing net on the first player or monster that steps on it. The victim becomes entangled and cannot move or attack until they either break the net or slip out of it. Some types of enemies are immune to nets (jellies, non-corporeal spirits, imps, giant spores, etc.), and thus are not effected by net traps. If you manage to spot it before it drops its net, it can be disarmed with the Traps & Doors skill.