Wondrous Item, uncommon

This nearly invisible strand of magic can be anchored midair without the need for physical support. Once placed, the Ethereal Tripwire spans up to 20 feet and can be attuned to trigger alarms, magical traps, or other effects when touched. Only those with the ability to detect magic can perceive it, and it can pass through objects or creatures harmlessly unless activated by a pre-set condition. Its spectral glow becomes visible only when the trigger is tripped, releasing the stored effect.