Muddle berries in a pint glass and add all ingredients except Guinness.
Shake with 2 kold draft cubes and strain into the pilsner glass.
Add crushed ice, swizzle a bit add more crushed ice and top with Guinness.
Source recipe is vague about type of berries, but presumably a mix of blueberries, strawberries, raspberries, and/or blackberries would be appropriate
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