Combine the chopped mango and the passionfruit juice in a blender and liquify. Pour into a small bowl and cover. Refrigerate for at least 1 hour.
In a blender, combine the frozen pineapple, creme de coconut, unsweetened coconut milk, lime juice, and ice. Blend until just combined. Place the blender pitcher in the freezer for 20-30 minutes until it just starts to harden.
In a tall glass, pour about 2 tablespoons of the mango-passionfruit puree in the bottom of the glass. Top with a splash of the dark rum.
Re-blend the piña colada mixture and pour over the mango-passionfruit-rum. Top with another splash of the dark rum. Garnish with a lime wedge.