We discovered quite some time ago that one of our cats, Fiver, loves playing fetch. He will run after a ball and bring it back until he’s exhausted. Not long after that, we learned to hide all the toy balls around nighttime, because if Fiver finds one and starts playing with it by himself, he gets into a pretty intense conversation with it. Loudly. Without concern for humans who might be trying to sleep.
A cat playing fetch? Really? Behold:
It might look as if he’s being remarkably obedient, but the truth is, he trained us, not the other way around. He figured out that if he dropped the ball near us, we would automatically throw it for him to chase. How convenient!
When he starts getting tired he often will try dropping the ball farther and farther away on his way back, in the hopes that will prompt us to do some of the work in coming to him instead of the other way around. A classic behavioral shaping technique. Occasionally it even works.