Mufasa is proof that cats don't always land on their feet.
Mufasa's Landing
Explanation
Explain Bear
Hey, dumb dumb, listen up! This joke is dark because Mufasa, who's basically a big cat (a lion, duh!), dies in "The Lion King." Usually, you think cats land on their feet, but Mufasa didn't make it. Get it now, bonehead?