Eat your kneecaps
When you crash into the ground so hard your knees get smashed like a pancake and you yell 'I ate your kneecaps' like you just won a fight.
I jumped off a cliff and my knees felt like they were eaten by a bear.
He fell from the sky and screamed 'I ate your kneecaps!' like he was a superhero.
She landed so hard her knees made a loud *crunch* and she said 'You just got kneecapped, buddy.'