This spell makes you effectively weightless to one particular flying creature (including but not limited to animal companions and familiars) allowing it to carry you without any impact on its speed or encumbrance. You must remain in contact with the creature and in the air at all times. If either of you chooses to break free, the creature lands, or it suffers damage, the spell ends immediately. Similarly, if you take damage or suffer any other sort of distraction you must succeed in a Concentration check in order to keep your grip. If the spell ends in mid-air, you fall to the ground in the exact same manner as an expired fly spell.

Since the spell eliminates weight as a consideration, it allows you to use creatures far smaller than yourself for transportation. In theory, assuming you find some way to communicate with it, even a housefly or bee could carry you to your destination. However, only one caster may use this spell on any given creature at a time. Even if the creature is large enough to carry multiple passengers, additional castings of the spell automatically fail and the weight of these casters affects the creature as normal.

Most creatures only consent to serve as transportation for this spell if specially trained (see sidebar) or are somehow persuaded to do so whether by magic or other means. If you have the ability to communicate with the creature, it must have a friendly attitude towards you in order to ferry you through the air. If you do not have the ability to communicate with the creature, it must have a helpful attitude instead.