1. Combine water and sugar in a saucepan over medium heat. Stir until the sugar is fully dissolved, creating a simple syrup. Let cool completely. 2. In a blender, combine the simple syrup, fresh lemon juice, and blackberries. Blend until smooth. 3. Strain the mixture through a fine-mesh sieve into a large pitcher to remove solids. Press down on the solids to extract as much liquid as possible. 4. Stir in the edible glitter if using, until well combined. 5. Chill the Witches Brew Lemonade for at least 2 hours before serving. 6. Serve over ice, garnished with fresh mint sprigs.