Cousin Mojo Addams is a relative of The Addams Family.
He was a not-so-professional escape artist whose unsuccessful last escape left him in a trunk at the bottom of the River of Doom. Gomez Addams was successful at beating all of Mojo's escape times.
It took him three days to extricate himself from the Full-Body Tourniquet of Doom. It took four weeks to escape from the Concrete Cocoon of Doom, but that's because he was waiting for his bones to heal. He was never able to escape the Buckled Blazer of Doom.
The New Addams Family episode: