Playbooks

Four Verticals out of Shotgun Wing Stack Wk sends all four eligible receivers vertical up the seams and numbers, with the two outside receivers on the left running a quick out and up while the diagram shows one release into a flat route before climbing, and the inside receivers on the right stemming straight up the seams. The running back stays in to check release and works a quick flat/swing route underneath as a hot outlet, giving the quarterback a checkdown if the deep routes are covered. This is a pure man and zone beater built to attack single high safeties and Cover 2 shells by flooding all four vertical lanes and stressing the safeties and corners deep, with the primary read starting on the seam routes and progressing outside to the boundary verticals before checking down to the running back.
Watch for two deep safeties splitting the field evenly pre-snap, which usually indicates Cover 2 or Cover 4 and tells the quarterback to attack the seams between the numbers and the safeties. If the free safety cheats to the middle of the field before the snap, expect Cover 3 or Cover 1, and the read should shift to the outside vertical or the breaking route on the boundary where the corner is isolated. Track linebacker drops after the snap, since a linebacker sinking into the seam lane can jump an underneath route and bait a turnover if the quarterback stares down that read too long. Man coverage shells with press corners and no safety help over the top are a green light to trust the vertical stems, but watch for a user controlled safety lurking in the middle who can rob the inside seam route. Disguised blitzes that show blitz then bail into zone coverage can confuse timing, so key the defensive line get off and linebacker spacing to confirm whether it is a real pressure package before committing to a deep drop.
Pre-snap, identify whether the defense is showing two high safeties or a single high look, since this concept is designed to gash Cover 2 and Cover 3 shells that cannot cover four verticals with only two or three deep defenders.
Key the middle linebacker depth and the safety rotation right at the snap, because if the safeties bail hard to the seams that usually signals Cover 3 and you should work the boundary verticals or the deep out breaking route on the left.
Use hot routes to convert one of the inside verticals into a slant or drag if you see man coverage with no safety help over the top, giving you a quicker win against aggressive man corners.
This play pairs well with RPO Peek Slant and RPO Alert Bubble from the same set, since defenses that sit back to defend four verts open up easy conversion RPO looks against light boxes.
Run this on early downs or obvious passing situations like second and long, since the deep shot potential is high but the checkdown to the running back keeps it viable on any down if the defense sells out to stop the pass.