The Riffel Rule is the effect of a key made by Hans Riffel. It is what disables an adult's ability to directly see magic, specifically the effects of the keys. It takes effect upon entering Keyhouse through the main door on the west side of the building.
The rule came into effect sometime after 1942, possibly after Hans Riffel used the Hercules Key to seriously injure or kill some men during World War II. Until Tyler Locke, Riffel was the final person to use the Whispering Iron to make a key.
The Riffel Rule only seems to apply to adults in a clear state of mind.
- Rendell Locke, as an adult, would frequently mention details of Keyhouse when drunk.
- Nina Locke, when drunk, was able to see and understand the effects of the Mending Key. She was also able to see and hear the ghost of Bode Locke.
- Ellie Whedon, mortally injured, was able to recall memories that had been removed using the Head Key.
- ↑ 1.0 1.1 1.2 Locke & Key: Clockworks #4, "The Whispering Iron". February 1, 2012
- ↑ 2.0 2.1 Locke and Key: Grindhouse. August 29, 2012
- ↑ Locke & Key: Welcome To Lovecraft #1. February 20, 2008
- ↑ Locke & Key: Crown of Shadows #6, "Beyond Repair". July 14, 2010
- ↑ Locke & Key: Omega #5, "The Fall". June 5, 2013
- ↑ Locke & Key: Omega #4, "Human Sacrifices". April 3, 2013
- ↑ Locke & Key: Keys to the Kingdom #6, "Detectives - Part 2". April 27, 2011