Preheat the oven to 350°F. Line a muffin tin with 12 cupcake liners to prepare for the perfect bake.

Whisk together in a medium bowl the flour, sugar, black cocoa, baking soda, and salt until well combined.

Combine warm water, vegetable oil, and melted butter into the dry ingredients, stirring until smooth and silky.

Incorporate an egg, buttermilk, and vanilla, mixing until the batter is uniform and smooth.

Divide the batter among the cupcake liners, filling each about ¾ full. Bake for 23-25 minutes until a toothpick comes out clean.

Allow them to cool on a wire rack.

Prepare a baking sheet with parchment paper and melt the chocolate wafers for spider legs.

Pipe 'L' shapes with the melted chocolate on parchment and freeze until set.

Crush Oreos and mix them with cream cheese to form a spreadable mixture. Roll this into 12 balls for the spider bodies.

Beat softened butter in a mixing bowl until pale; gradually mix in powdered sugar, black cocoa, and salt until light and fluffy.

Frost cooled cupcakes generously, sprinkle with white sprinkles, and attach the spider bodies and legs for a fun and festive finish.