A Sky Trainer asking to have a Sky Battle with the player
A Sky Battle (Japanese: スカイバトルSky Battle) is a type of Pokémon battle exclusive to Pokémon X and Y. Sky Battles consist of two Pokémon battling each other in the air instead of on land or sea. However, because of this, only certain Flying types and certain Pokémon with the Ability Levitate are eligible for Sky Battles.
This section is incomplete. Please feel free to edit this section to add missing information and complete it. Reason: Does the player black out normally if they lose when their whole team is eligible?
At certain points in the game, the player can encounter Sky Trainers on top of cliffs or other distant areas who will challenge them to a Sky Battle. All Sky Battles are optional, since the player may not have any eligible Pokémon to use. If all eligible Pokémon in the battle faint, the player will black out, but will resume the game standing where they were before battle. In this event, the Sky Trainer is unable to be re-challenged or even spoken to, even if the player's eligible Pokémon are restored, until the player exits and reenters the area.
Eligible Pokémon
Most Flying-type Pokémon and Pokémon with the AbilityLevitate are eligible for Sky Battles. If a Pokémon can have Levitate as one of multiple Abilities and is not Flying-type, it will only be eligible if it has Levitate (this affects only Duskull, Bronzor and Bronzong). Pokémon do not lose eligibility even if they are holding an item like Iron Ball, and cannot gain eligibility by holding an item like Air Balloon. Eligibility is determined before the battle starts, so Pokémon that must first Mega Evolve to become Flying-type or have Levitate are not eligible. Eligibility cannot be changed in-battle, and will be unaffected by a Pokémon becoming grounded due to any in-battle effect, such as Mega Evolution, a held item change, or a move like Roost or Gastro Acid.
Certain Flying types and Pokémon with Levitate are ineligible for Sky Battles, such as Gengar and Hawlucha. These Pokémon are not shown flying or hovering in normal battles.
Certain moves are not permitted to be used in Sky Battles. If a Pokémon's only usable moves are prohibited, the Pokémon will use Struggle if it attempts to attack. If one of these moves is called by Metronome or Sleep Talk, a message will appear saying that it won't work well in Sky Battles.
Sky Battles first appeared in Battles in the Sky!. An expert Sky Trainer called Moria was seen defeating another Sky Trainer's Skarmory with her Talonflame. Later, Ash challenged Moria to a Sky Battle, wanting to use his Fletchling against Talonflame. Although Moria accepted the offer, Talonflame was shown being unwilling to battle against its pre-evolved form, forcing Ash to use his Hawlucha instead. Even through Hawlucha tried its best, it was defeated rather easily. After that, Team Rocket showed up, trying to steal Talonflame, but were soon defeated. Afterwards, Talonflame, being thankful for Ash's Fletchling for saving it, accepted Fletchling's battle challenge. Even though Fletchling was almost defeated by Talonflame's Fire Blast, it evolved into a Fletchinder and learned Flame Charge partway through the battle, allowing Ash to gain the victory.
During Sky Battles, Trainers take to the air using special suits so they can fly alongside their Pokémon. Unlike the games, in which certain Flying types or Pokémon with Levitate are restricted, Sky Battles appear to be open to any Pokémon which has the ability to fly; both Hawlucha and Fletchling took part in the anime, which cannot participate in the games. Hawlucha also used Flying Press, a move which is prohibited in the games, although it missed.
Sky Battles first appeared in Burning Fletchinder. While flying on a helicopter, X, Y, Trevor, Shauna, Tierno, and Cassius were attacked by a group of Sky Trainers led by Yvette. Commanding a herd of Vivillon, they attacked the helicopter with Hurricane, forcing Y to go out and battle with them. Y flew away from the helicopter to prevent it from being attacked, but Yvette caught up to her and started to bully her, while her Vivillon battled Fletchy. Y finally fought back as Fletchy evolved into Fletchinder, who defeated Vivillon with Flame Charge. At the same time, X and the others saw Celosia's Aegislash, realizing that all the Sky Trainers were under its mind control. After X had Élec defeat it with Discharge, the Sky Trainers were freed from its control.
Trivia
12 of the 18 types lose at least one move in Sky Battles. The only types whose moves are all allowed in Sky Battles are the Bug, Dark, Dragon, Flying, Ghost, and Ice types.
Five Pokémon lose their eligibility to participate in Sky Battles by evolution or form change: Gengar, Scizor, Dusclops, Giratina Altered Forme, and Arceus.
The only Flying/Levitating Pokémon that does not stand on the ground in battle yet cannot participate in Sky Battles is Mega Pinsir, due to its non-Mega Evolved form needing to be in battle first.
