Flood

The concept

Three routes to one side at three depths — flat, out and sail — stacked in a single vertical slice of field.

The offense1 / 3
The look
Three receivers to one side and nothing to the other. The flat runs immediately, the out climbs to eight before it breaks, and the sail keeps going — three routes leaving at three different heights, all inside one throwing window.
vs Man2 / 3
The conflict
Three routes, three defenders, nobody wrong. Against man a flood is three separate races down one sideline.
vs Man3 / 3
The throw
High to low. Look at the sail first; the moment a defender commits, the level above or below him is open.

Why it works

Three levels, two defenders
The flat at two yards, the out at eight and the sail at fourteen sit in one vertical slice of field. A zone side has a flat defender and a deep defender to cover it. Two into three does not go, and no amount of effort fixes arithmetic.
You read one man, not a coverage
You are not diagnosing Cover 2 or Cover 3 at the top of your drop. You are watching the flat defender widen or sink, and throwing the level he left. That is why flood holds up for a quarterback who is still learning to read a defense.
The stretch is vertical, so it travels
Concepts that pull a defense sideways need width you may not have. Flood stacks its routes on top of each other instead, which is why it works out of trips, out of a bunch, off play action, and at any team size that can get three receivers to one side.

Running the levels too close together
If the out drifts up to twelve yards, it and the sail become one route and one defender covers both. The gaps between two, eight and fourteen are not decoration — they are the concept.
Looking for the sail and throwing it anyway
The deepest route is the slowest to arrive and the easiest to jump. Work high to low with your eyes, then expect the out to be the throw. The sail is what makes the corner leave; it is rarely the answer itself.
Calling it against man
Three routes to one side against man is three one-on-ones on a crowded sideline, with nobody put in a bind anywhere. Flood is a zone call — press Man above and watch the conflict disappear.

The written breakdowns, by format. The diagram above is the same at every team size — these are the pages that say how it is actually run at each.

Open it in the designer, change the routes, save it to your playbook.