Item from Invincible by Robert Kirkman
A sonic device designed to incapacitate or kill Viltrumites — Cecil's insurance policy against the gods he works alongside.
The Kill Switch is Cecil Stedman in device form: pragmatic, hidden, and designed to destroy the people he works with if they become a threat. It targets the Viltrumite vulnerability to high-frequency sound, causing intense pain, disorientation, and potentially death with sustained exposure. Cecil had one implanted in Mark without his knowledge or consent — a contingency that perfectly encapsulates their relationship. Trust and betrayal, cooperation and control, all contained in a device smaller than a thumbnail.
A small, implantable device — easily concealed, easily forgotten about until it activates. Emits a targeted high-frequency sonic pulse tuned to exploit Viltrumite physiology. Discreet enough to hide in someone's body without their knowledge.
Also known as: Kill Switch, Cecil's Kill Switch, Sonic Kill Switch