Dispel Trap

From The Heretic Knowledge Vault

One of the magical defenses at the Heretic Knowledge Vault, set up to keep intruders (like, say, Meji Hinadori) from gaining access to the secrets therein. She triggers it when she attempts to gain entry invisibly, becoming visible to the NPC Guards and thus sparking all manner of fun and violence.

It isn't clear whether this trap is a magical gadget or a non-gadget-based magical effect, so it's placed in both categories for completeness.