In a mixing bowl, combine the softened cream cheese and shredded cheddar cheese, mixing until smooth and well incorporated.
Add garlic powder and black pepper to the cheese mixture, folding gently to distribute the seasonings evenly.
Transfer the cheese mixture onto a piece of plastic wrap and mold it into a round ball, smoothing the surface with your hands.
Once chilled, unwrap the cheese ball and place it on a serving platter.
Break pretzels into smaller segments to resemble spider legs and arrange them around the cheese ball to create a web-like spider shape.
Attach googly eyes to the top of the cheese ball using a small dab of cheese or a tiny amount of water for adhesion.
Ensure all pretzels and eyes are secured and arrange the spider on your serving platter for presentation.