Pendulum is a transformation that both Kirby and Prince Fluff can take on in the game Kirby's Epic Yarn. The two can transform into this form while pressing the 1 button near a brass button and latching on to it with their Yarn Whips.
Kirby becomes a pink and red pendulum while Prince Fluff becomes a blue and orange one. Their legs and arms disappear, but their faces are still visible.
Using the yarn whip on brass buttons will transform Kirby and Prince Fluff into this form, and enable them to swing side to side by pressing left or right on the +Control Pad. In the level Fountain Gardens, they can swing to knock down beads from a certain tree by latching onto one of the buttons. The yarn whip must be used to enter this form, so Kirby or the Prince cannot retain their yarn balls if they wish to use this form. The yarn ball can be tossed, or put on the ground by crouching. This is also an essential move, as it is needed to ring the Bonus Bell to end each stage.