From Sonic Retro
In Sonic Adventure 2, the Booster is an upgrade to Miles "Tails" Prower's walking mech. It enables the mech to hover short distances after jumping. It is necessary to complete the level it is located in: Mission Street.
To get the upgrade, proceed through Mission Street until encountering a large gap in the road that can't be jumped across with a line of rings. Turn around from the gap to find the Booster on a platform behind a small road. Be careful when getting it as the road will collapse, requiring you to fly after you pick it up. Fly over the large gap to continue on with the level.
|Character upgrades in Sonic Adventure 2|
|Sonic||Light Shoes | Ancient Light | Bounce Bracelet | Flame Ring | Mystic Melody | Magic Gloves|
|Tails||Booster | Bazooka | Laser Blaster | Mystic Melody|
|Knuckles||Shovel Claw | Air Necklace | Hammer Gloves | Sunglasses | Mystic Melody|
|Shadow||Air Shoes | Ancient Light | Mystic Melody | Flame Ring|
|Eggman||Jet Engine | Large Cannon | Protective Armor | Laser Blaster | Mystic Melody|
|Rouge||Pick Nails | Iron Boots | Mystic Melody | Treasure Scope|