Completing A-B-C-D lights the middle side lanes (A and D) for Special.
Hit pop bumpers in order. 1-2-3 lights left sling for 100K. Next, 4-5-6 lights right sling. Last, 7-8-9 lights the center pop for 100K.
Beware of the opens area under the flippers. Draining through them means missing out on the 500K you'd otherwise get for a center drain.
