Famous Slushes makes up the core of Sonic's Slush menu and includes the following flavors: Minute Maid Cranberry, Powerade Mountain Berry Blast, Green Apple, Blue Coconut, Cherry, Grape, Orange, Watermelon, and Blue Raspberry.
The Transformers: The Last Knight Slushes are a limited-time series of color-changing Slushes named after key Transformers from the upcoming movie. The available varieties are: Optimus Prime (cherry with blue raspberry on top), Bumblebee (orange with grape on top), and Megatron (clear slush with grape on top).
Photo via Sonic.