Stir the refried beans and taco seasoning together in a bowl until evenly combined.
Spread the bean mixture into an even layer in a shallow serving dish.
Spoon the guacamole over the beans and smooth it into a second layer.
Sprinkle the shredded cheese evenly across the guacamole.
Spread 3/4 cup of the sour cream over the cheese to form the top layer.
Place the remaining 1/4 cup sour cream into a small zip-top bag, snip off one corner, and pipe concentric circles on the sour cream surface. Draw lines from the center outward to create a web pattern.
Arrange a few black olive slices in the center to form a simple spider shape.
Set the dish on the table with a bowl of tortilla chips for serving.