Star, true to herself, got tired and walked out of the room. She does this, she will play like mad for a little while, then take a break, then come back. Usually two or three times, then she's done. Leo does this too, but it's not as obvious because he doesn't leave, he just lays down and plays lazily for a while, grabbing it only when it practically lands in his paws.
I've heard Jackson Galaxy call this something like diminishing returns. Cats, depending on their age, will play like wild, take a break, then play like wild for a shorter period of time, another pause and back again. Star's limit is three times back to play. Leo is nearly unlimited, though he does get slower and less active in that play each time.
Anyway, back to the other day. I was still playing with Leo on the bed. I will either swing the Stringy around in circles around him, making him run in circles until he catches it, or I will 'whip' it back and forth and he will dive on it when it's on the side he wants to attack. When I do the whippy thing, he will jump on it, full length, facing the whipped end where he gives it the bitey. When I do the circle thing, he grabs at it with both paws and teeth and hangs on.
However, when Star is also in the room, he is much lower key, trying not to attract her attention and thus inviting attack. So I was swinging the string back and forth past him and he'd grab it and put the bitey on it. He had it pinned down under both paws when Star left the room. He had a good hold too, as I couldn't get it away from him.
Since Star was gone, Greg brought up his Stringy to tease Leo with too. Leo went wide eyed at TWO Stringies, gave the one under his paws a startled look and JUMPED up! EEK!
He sat up straight on the corner of the bed and eyed those two Stringies as if they were aliens from another planet sent to suck out his life force! Seriously! It was so funny, we couldn't help but laugh at him! Poor baby!
This my Stringy! Don't know where that impostor came from.. don't care!
(Leo's always dangling his head off the bed like this, Stringy or no, he must like how things look upside down..)
That whole incident.. probably another thing I don't wanna talk about..