Sprinkleshell first appears in the Episode Home Sticky Home, in Level 301.
He is a cyan (blue) colored turtle whose brown shell is covered with sprinkles of colourful spots.
When you start the level, his head is shrunk.
The energy bar under him needs to be charged.
To do this feed him with cyan colored candies.
It means you should match this color candies.
When the power bar is full, Sprinkleshell will extend his head, and you can click him to change color of the candies you want to destroy.
Sprinkleshell will then remove all this color from your board!
He is similar to a combination of color bomb and a regular candy, but does not use up any moves to do it.