Pour the Gatorade bottles into the blender.
Add the ice cubes to the blender with the Gatorade.
Secure the lid on the blender and blend on high speed for about 30-45 seconds, until the mixture becomes thick, slushy, and smooth with a frosty appearance.
Stop the blender and check the consistency; it should be icy, with a semi-crumbly texture. If it's too thick, add a splash of water and blend briefly to loosen it.
Pour the slushie into chilled glasses or bowls, using a spoon if needed to transfer it smoothly.
Serve immediately with a colorful straw or spoon, enjoying the vibrant, frosty treat.