Preheat the oven to 375°F (190°C).

Lightly grease a 9-inch round baking dish or oven-safe skillet.

Combine softened cream cheese, buffalo sauce, and ranch dressing until mostly smooth.

Stir in garlic powder and onion powder.

Fold in shredded cooked chicken.

Mix in ¾ cup cheddar and ½ cup mozzarella.

Transfer to the baking dish and smooth the surface.

Sprinkle the remaining cheddar and mozzarella over the top.

Bake uncovered for 18–20 minutes, until hot and bubbling around the edges.

Meanwhile, transfer sour cream to a piping bag. Thin with 1–2 teaspoons milk only if necessary.

Remove the dip from the oven and allow it to settle for 2–3 minutes.

Pipe a small sour cream circle in the center, followed by progressively larger concentric circles.

Starting near the center, drag a clean toothpick outward through the circles. Repeat around the dip to create a spider-web pattern.

If desired, create a small spider from sliced black olives and position it on the web.

Garnish the outside edge with green onions.

Serve warm with tortilla chips, vegetables, crackers, or toasted bread.