Periwinkle is a Premium Box Tsum. She is currently only available on the Japanese version. She is a Limited Event Tsum and is not available from purchasing Premium Boxes outside of the event. She was first introduced during the Japan Event Seasons of Pixie Hollow (June 2019).
Periwinkle will take one type of Tsum and turn it into a Special Bomb. Her base radius is S and her base number required is 21. Higher Skill levels reduce the number required.