In a blender, combine 1 cup of blackberries with a splash of pineapple juice, blending on high for about 30 seconds until smooth.

Pour the blended blackberry puree through a fine sieve into a bowl, using the back of a spoon to extract as much liquid as possible.

In a cocktail shaker, combine the strained blackberry puree with 2 ounces of Lyre's Non-Alcoholic Spirit and around 4 ounces of remaining pineapple juice. Shake vigorously for about 15-20 seconds.

Fill a spooky glass with ice cubes, then pour the blackberry mixture over the ice to create a layering effect.

Drizzle blue syrup gently over the top, garnish with a lime slice and mint sprig.