Sky Chase (スカイチェイス Sukaicheisu?) is a sub-game stage from Sonic Adventure. Sky Chase is played while Sonic and Tails chase Dr. Eggman's Egg Carrier in the Tornado (and, later, the Tornado II). The point of Sky Chase is to survive the onslaught of enemies and gain as many points as possible. Sky Chase is named after the Sky Chase Zone from Sonic the Hedgehog 2, which also involved Sonic and Tails in the Tornado, fending off Badniks.
After Dr. Eggman stole two Chaos Emeralds from Sonic and Tails after they fought Knuckles, he used the Emeralds on Chaos who became Chaos 4. After Chaos was defeated, Eggman escapes to the Egg Carrier and Sonic and Tails give chase in the Tornado, this where the first act takes place.
After Sonic finishes the Red Mountain stage, he sees Tails in the new Tornado and they give chase again (Act 2). When Sonic and Tails reach the back, Tails reveals that the Tornado II can transform into attack mode. The Tornado II is faster and stronger which the two use to disable the cannon and land on the Egg Carrier, unfortunately, Tails forgot that the Tornado II has no landing gear in that mode and they crash.
In both acts of Sky Chase, the player has endless amount of machine gun built inside the Tornado, and can lock-on the enemies before giving shots (six closures as a maximum). The tornado has a health gauge which depletes by each shot it gets. If the health gauge meter reaches zero, the player loses 1-Up.
The theme of the act has a blue backdrops while taking place high in the sky above the clouds. Once the player starts, he will fly toward the Egg Carrier while overseeing that there are small troops of white planes flying toward the player (which sometimes have a yellow one as a leader in the center). Those planes will keep going to the Tornado in every section of the stage. The next section, the Tornado will fly across the back top of the ship which has several missile launchers ready to fire at the player. In the next sections, the player will fly toward the right wing, front top of the ship, and the left wing of the ship which are flooded with a lot of missile launchers and several falling down planes.
In this act, the player flies in a dark-cloudy sky theme where huge troops of planes fly out of the screen, from the Egg Carrier, and toward the player. It starts much like the first act, but toward the front top of the ship, to the back of the ship. Here, the player controls the Tornado II, with a lot of missiles and planes rounds are fired at the player. Afterward, the tornado II will change to its attack mode and heads toward the ground part of the ship, where mines take place.
In the next sections, the tornado will take several sorties at different angles of the ground part, front, and across the wings of the ship (all which are heavily guarded). Then the tornado returns to fly toward the front of the Egg Carrier crossing the ground part which is heavily guarded with missiles turrets, mines, and mechanical arms.
During the final section of the act, the player will directly attack the cannon of the ship before it does so, while avoiding incoming missiles. Here, the best strategy is to keep shooting the weapon when the huge doors open, and then move away of the laser's way.
The Points awarded for each target shot down in both acts are as follows:
- Both Sky Chase and its second act are both modeled after another of Sega's video game series, Panzer Dragoon. Although the controls are simplified in comparison, the basic control scheme between the two games is the same.
- Sky Chase is one of two stages in Sonic Adventure and Sonic Adventure DX: Director's Cut to be named after past zones in the Sonic franchise, the other one being Ice Cap.
- Sky Chase is named after the Sky Chase Zone from Sonic The Hedgehog 2, sharing more than just the title. It employs the same idea of fighting flying enemies and chasing an aircraft made by Dr. Eggman.
- This Sub Game is accessible to Sonic and Tails only.
- Originally, there was going to be a mechanical dragon miniboss in Sky Chase, but was scrapped because of difficulty and time restraints. This is shown if 'E' (center camera) is held during the level.
- Through hacking, when he is loaded into the game, he is revealed to only have his flying animation completed, he does not have any attacks. He simply just flies behind the Tornado and does nothing else, meaning he was scrapped very early in production. It is unknown what he eventually would have done since he is incomplete, although it is possible that at one time he could have been the reason why the Tornado was shot out of the sky.
- In Sonic the Hedgehog 2, the player can control Sonic or Tails (depending on who they pick) and the other will fly the Tornado, but in Sonic Adventure and Sonic Adventure DX: Director's Cut it doesn't matter who you select; Tails will always fly the two planes and Sonic will stand on them.
- In the Japanese audio of the game, Sonic and Tails will scream in a panic as the Tornado spirals out of control. In the English audio however, they respond with excitement.
- During the production of the Dreamcast version, Sonic R/Sonic Jam models were used in this stage as placeholders. This is seen in pre-release screenshots of the game. In the final version, the models are still noticeably lower-poly than the usual ones and look only slightly modified from the Saturn ones (to include green eyes for Sonic). The DX version uses the same higher-poly models as the rest of the game during Sky Chase.