Linnéa uses a yoga ball

Here's a description of the contestant's attempt. Someone's probably working on collecting some images to illustrate it.

Linnéa grabs a yoga ball from the shed. It’s unclear if she gaffer-taped the key to the ball, or if she cut a small slit into the ball, dropped the key inside, and taped the slit back up. She takes the ball down to the water but, instead of heading to the dock, wanders through a section of thorny plants on a small cliff – injuring herself in the process, and nearly sliding off of the cliff – and throws the ball into that section of the water.

(Written by Jenny R and edited by Karl Craven)