You are at least 5 feet above the heads of one or more creatures. This is not the same as them having the Prone condition or being a different size than you; it only applies if you are positioned at a higher elevation than them, and the lowest part of your body is above where the tallest part of their body would be if they were not Prone.
You gain a +2 Bonus to Defense and Reflex saving throws against any non-Curse, non-Area attacks of creatures below you, as well as to any saving throws against Maneuver attacks that do not target your Will saving throw by such creatures.
You gain a +2 Bonus to your non-Curse, non-Area attack rolls against creatures below you.