An old lion was stalking a horse, but he was no longer strong, so he decided to play a trick instead.
"I'm a doctor," he shouted to the horse, "and I see that you're limping."
The horse, however, was also a trickster. "What good luck!" he said. "I've got a thorn in my hoof. Please remove it if you can."
Then, when the lion bent down to inspect the hoof, the horse kicked him in the head and ran off.
"That horse tricked this old trickster, fair and square," said the stunned lion, "and I've got only myself to blame."
Inspired by: Mille Fabulae et Una, a collection of Latin fables that I've edited, free to read online. I am not translating the Latin here; instead, I am just telling a 100-word version of the fable.
Notes: This is fable 6 in the book, which is Perry 187. It is sometimes told about a wolf instead of a lion.