They say that hypnosis alone cannot compel a pony to do anything against their will. But in an Equestria ruled by mares, every stallion has a deep-rooted instinct to surrender to a dominant mare, and hypnosis puts a pony in a state of mind that makes it easy and natural to act on an instinct. The right words can have an intoxicating effect that massages away inhibition. And once the pony is in a state of trance with his defenses down, the hypnotist can mercilessly stimulate that hidden desire and associate its indulgence with her voice. Unicorn mares often slip in a spell or two to magnify the stallion’s desire, making the effect of the hypnosis almost unfightable.
 
A well-executed hypnosis will plant a completely subconscious trigger. The stallion will feel a powerful compulsion to do whatever the mare asks, but won’t know why. All he will know is that she commands a power over him unlike any other mare, and he has no means to break her spell… not that he will want to break it once he finally tastes the pleasure of obedience.