Here are some tips that will unlock additional characters in Sonic Adventure.
Knuckles
The defeat after finishing the level Ice Cap in the skin of Sonic or Tails .
Super Sonic
Complete the game playing as Knuckles , Amy , Sonic , Tails , E -102 Gamma and well Big . Super Sonic will be available only in the mode " Adventure " .
Big
Embody Sonic and beat Chaos 6.
Details
Overcoming the mission C level Emerald Coast in 's skin Sonic .
Amy
Finish the level Sky Chase and then go talk to Amy in the casino playing as Sonic.
E -102 Gamma
Complete level Sky Deck then beat Gamma in the skin of Sonic or Tails .
