What cocktail can I make with butterscotch liqueur, milk, dark rum, vodka, and orange juice?

It looks like you're in the mood for a cocktail that combines rich, sweet, and creamy ingredients with a hint of citrus. While you have quite a diverse list of ingredients, there's not a single cocktail among the ones you provided that uses all of them together. However, we can get creative by suggesting a few that utilize most of them or give you an idea for modifications.

The "Pirate Milk" could serve as a great base to work with. It features butterscotch schnapps and dark rum, and you could creatively add a splash of milk, which isn't originally part of that recipe, but could enhance the creaminess and mimic the presence of Amarula Cream. However, it doesn't use orange juice or vodka, so you'd have to decide which flavors you want to emphasize.

For a combination that uses both butterscotch and vodka, consider a twist on the "Chocolate Orange." Though it traditionally uses Vodka, Creme de Cacao, and orange juice, you could experiment by introducing a bit of butterscotch liqueur to add a caramel note to the citrusy, chocolate blend.

If you're enthusiastic about using all your ingredients, you might consider crafting a custom drink that incorporates elements from these popular cocktails. Start with a base of vodka and dark rum, introduce the silky sweetness of butterscotch, add a touch of orange juice for a citrus punch, and finally top it off with milk to integrate all those flavors smoothly.

Remember, cocktail making is as much about experimentation and personal preference as it is about traditional recipes, so feel free to adjust proportions to suit your taste!