This short excerpt from Ableton's Learn Live series focuses on the Tides algorithm inside Hybrid Reverb, walking through the specific parameter choices that produce a phasey, pumping modulation effect on a reverb tail.
Setting the rate to quarter notes gives the pumping a rhythmic lock, while pushing the Tide amount to 100% makes the effect unmistakable. Flipping the phase to 0 degrees keeps the left and right channels in sync rather than creating a wide swirl, and pulling Damping down lets higher frequencies survive through the tail.