Here are all the guides, tips, and strategies to enjoy playing Sonic Adventure with unlockables and cheats.
Unlockables
Characters
| Character | How to Get |
| Tails | Complete Emerald Coast Mission C as Sonic |
| Knuckles | Defeat him in battle as Sonic or Tails in Adventure Mode |
| Amy | Speak to her in the Casino as Sonic after finishing Sky Chase |
| Big | Defeat Chaos 6 as Sonic in Adventure Mode |
| E-102 Gamma | Defeat him in battle as Sonic or Tails in Adventure Mode after finishing Sky Deck |
| Super Sonic | Beat Adventure Mode with all characters |
Upgrades
| Upgrade | How to Get |
| Ancient Light (Sonic) | On top of a rock on Angel Island. |
| Booster (E-102) | In the Weapon’s Armory on the Egg Carrier. |
| Crystal Ring (Sonic) | Walk up the steps in the Hotel, press the two buttons and use the Light Speed dash. |
| Fighting Gloves (Knuckles) | On a ledge over Big’s house. |
| Jet Anklet (Tails) | Behind Twinkle Park, look for a hole in the ceiling of the sewer. |
| Laser Blaster (E-102) | In the Restricted Room on the Egg Carrier (crash site). |
| Life Belt (Big) | In the entrance to Ice Cap. |
| Light Speed Shoes (Sonic) | In the Sewer near the battle with Chaos 0. |
| Long Hammer (Amy) | Beat your own high score on Hedgehog Hammer after the Egg Carrier crashes. |
| Long Rod (Big) | Under the bed in Big’s house. |
| Lure Upgrade 1 (Big) | In the sewer behind Twinkle Park. |
| Lure Upgrade 2 (Big) | Under a sheet of ice in Ice Cap. |
| Lure Upgrade 3 (Big) | In a cave in the Mystic Ruins (forest area). |
| Lure Upgrade 4 (Big) | In a jail cell on the Egg Carrier. |
| Rhythm Badge (Tails) | In the flashback with Tikal. |
| Shovel Claw (Knuckles) | In the tunnel with the cart leading to the Mystic Ruins Chao Garden. |
| Warrior Feather (Amy) | Beat Eggman’s high score on Hedgehog Hammer. |
Chao eggs
Silver Chao Egg – In the Mystic Ruins, visit the waterfall in the middle of the Adventure Field. Push the stone sticking out of the wall to the right. A silver egg drops behind the waterfall and starts floating to shore.
Gold Chao Egg – In Station Square, go to the spot where you fight Chaos 0. Look to the side of the entrance to City Hall to find a rock shaped like an egg. Pick it up and take it to the building on the left of City Hall. Replace the rock with the egg, and the door will unlock, allowing you to get the Gold Chao Egg.
Black & Blue Chao Egg – In the Egg Carrier, go to the jail area where Amy was held. Step on the switch to open the door next to Amy’s cell.
Special Chao – Collect at least 100 emblems to access the Black Market and purchase the Special Chao.
Chao moods
| Sign | Mood |
| Heart | Happy |
| — over eyes | Happy |
| Swirl | Angry |
| XX over eyes | Angry |
| Flailing arms | Angry |
| Question mark (?) | Confused |
| Exclamation point (!) | Surprised |
| Half-closed eyes | Tired |
| Waving arms | Wants attention |
Cheats
The game is enjoyable by itself, but cheating makes it even better. Always keep in mind to input codes with a GameShark. All the below codes are compatible with most emulators.
Note: before entering cheats, be aware that altering the game can cause random freezing and several other glitches.
Infinite Lives
Cheat code:
86D39645
00000009
999 Rings
Cheat code:
D3D8989A
000003E7
Unlock Tails & Knuckles
Cheat code:
274F7B2C
00000101
Unlock Amy & E-102 Gamma
Cheat code:
49DA07A0
00000101
Unlock Big & Super Sonic
Cheat code:
7E1DCB6B
00000101
Skating Sonic
Cheat code:
44923941
0000000E
44AA3941
0000000E
Sonic Adventure is an action-platforming game by SEGA released for Dreamcast worldwide in 1999. An enhanced version, Sonic Adventure DX: Director’s Cut, was released worldwide for the Nintendo GameCube in 2003, PC in 2005, Xbox 360 and PlayStation 3 in 2010.