The Air Boost is a move in the Sonic the Hedgehog series. It is an airborne variation of the Boost that is used to increase the user's speed in midair and fly immense distances.
When performing the Air Boost, the user surrounds themselves in a fiery energy shield while in midair and propels themselves forward at speeds beyond the sound barrier, thus turning the user into a highly destructive midair projectile. The color of the energy field depends on the user; for example, Sonic's is (usually) blue, while Shadow's is yellow. This moves not only allows its user to plow through midair enemies but also lets them move great distances through midair in pseudo-flight.
In gameplay, the Air Boost is an offensive maneuver that can be used to both attack enemies and traverse the environment, the latter allowing the player to cross gaps or reach midair objects. However, the user does not immediately stop moving when landing from an Air Boost, which brings the player at risk of moving into unwanted areas, like hazardous obstacles or bottomless pits. Additionally, the player can only perform the Air Boost once for every ascension into midair, and only if there is energy in the Boost Gauge to power it. The length of time the Air Boost can be maintained on the air is dependent on the game.
In the Wii/PlayStation 2 version, the player can perform the move at any time, while in the Xbox 360/PlayStation 3 version, the player must have obtained the Air Boost Shoes before being able to use it. Once the player can perform the Air Boost in the Xbox 360/PlayStation 3 version, the move overrides Sonic's ability to perform the Jump Dash until the Ring Energy Gauge is empty. In gameplay, the Air Boost's range is very long, and using it on the Xbox 360/PlayStation 3 version creates a brief distortion (although it can only be used in small bursts).
To use the Air Boost in gameplay, the player has to press the following buttons in midair while there is energy in the Boost Gauge/Ring Energy Gauge:
In gameplay, the Air Boost retains its range from Sonic Unleashed. On the Wii version, the Air Boost can be used continuously for a period of time, although it will eventually wear out if the playable character does not touch the ground soon enough. This cannot happen in the Nintendo DS version.
To use the Air Boost in gameplay, the player has to press or hold (to maintain the Air Boost more in the air) the following buttons when in midair while there is energy in the Wisp/Boost Gauge:
Wii Remote + Nunchunk
Wii Remote Sideways
Wii (Classic Controller)
Wii (GameCube Controller)
In Sonic Generations, the Air Boost is one of Modern Sonic's maneuvers. On the console/PC version of the game, the Air Boost has the same appearance and distortion effect it had in Sonic Unleashed, but its range is shorter and it is less controllable. It can also only be used in small bursts. To use it in gameplay, the player must press / in midair while there is energy in the Boost Gauge, though it depletes approximately 20% of the Boost Gauge when triggered. Modern Super Sonic can use the Air Boost without depleting the Boost Gauge, though it will increase his innate Ring consumption mechanic.
In the Nintendo 3DS version of Sonic Generations, the Air Boost visually looks like the game's version of the Boost and will create a small distortion effect when used. To perform it in gameplay, the player must press in midair while there is energy in the Boost Gauge. Unlike its console/PC counterpart, however, the Air Boost does not automatically deplete the Boost Gauge by 20% when used. In addition, its range can be extended for as long as is held. This makes it possible to crush enemies in the way of Sonic while he is using the move until he lands on the ground. Additionally, he can continue using it as the normal Boost upon landing.
In the game's storyline, Modern Sonic used this technique to catch the red Chaos Emerald in midair, which left Classic Sonic thoroughly impressed. At the end of the game, Classic Sonic wanted to show his counterpart that he had learned the Air Boost. Though he could not fully pull it off, Modern Sonic still praised him and promised he would only get better.
In gameplay, the Air Boost retains its distortion effect while in use, but the move's range and functionality are changed considerably. When the player triggers the Air Boost, Sonic/Shadow will charge ahead while ascending a little above their jump's altitude at first then start descending toward the ground. In this game, they can maintain the Air Boost until they touch the ground, and continue using it there as the Boost. To perform the Air Boost in gameplay, the player must press // in midair while there is energy in the Boost Gauge.
In the opening scene of the Sonic Episode in Sonic the Hedgehog (2006), Sonic is seen with a midair aura around him when he was fighting Eggman's robots. It is unknown if this is the Air Boost or just a vapor cone.
If the player uses Super Sonic in Sonic Generations, then turns back in the direction they came from and performs the Air Boost, it will make Super Sonic dash in the air, but forward on the path instead of backward.
In Sonic Colors, it is possible to get an Item Box without touching it by Air Boosting at the platform it is standing on.