G1 ID Tail Action
From My Little Wiki
Happy Tails
She has a hard plastic ring around her tail. Her tail spins when you squeeze her.
Dance 'n Prance
She has a knob on her chest!
Brush 'n Grow
You can pull her tail out longer and make it shorten by cranking her head. If she also has a jewel on her forehead, scroll down to the Princess brush 'n grow ponies.