In the heat of battle, Night Elf Archers can call upon the mighty Hippogryphs to carry them into the air. The Archers mount the flying beasts and are capable of firing their arrows from the Hippogryphs' backs. The brave creatures respond to the female riders as if they shared an empathic bond.
Archers transition well into Hippogryph Riders. Get an expansion then build 2-3 Ancients of Winds. Hot key these buildings and set the rally point on your Hero. Continue to make Hippogryphs by queuing them up. As they are created they will move to your Hero and Archers where you can match them up to create Hippogryph Riders. Eventually you can convert all of your Archers to Hippogryph Riders. This may not be wise to do if the enemy is prepared with Crypt Fiends with Web, Raiders with Ensnare, or other things that can easily kill air units. Keep in mind that by turning your Archers into Hippogryph Riders you can do attacks on enemy towns from the backside (away from towers). You are also creating Archers with the same damage but that cannot be hit by melee units, have greater sight, are faster, and that have more hit points. The only downsides of Hippogryph Riders vs Archers is 10 less range and a new weakness to anti-air abilities.
Since your Hero does not fly it can be challenging to use a Hero and Hippogryph Riders. One way to do it is to control the Hippogryph Riders and have the Hero set to follow them. You can also use Control Groups.
Use the standard ranged unit techniques as you do with Archers, Dryads, and Huntresses. It can be even easier for Hippogryph Riders since they don't have to worry about melee units.
Whenever possible attack enemy towns from over trees or other areas that ground units cannot reach. You can sometimes sneak into the back sides of towns that are not protected by towers and kill off enemy workers, Town Halls, Entangled Gold Mines, or Haunted Gold Mines, then run.
Research all of the upgrades for the Hippogryph Riders. If you are going to spend that much money creating them they should be the best they can be.
Archers can dismount from the Hippogryphs. This allows both units to attack on their own. You may find this useful in certain situations, such as when facing other air units.
Spells & Abilities
The Hippogryph Rider will be affected by upgrades from the Archer, so if you did research the Archer upgrades: Improved Bows and Marksmanship, it will also effect the Hippogryph Rider.