Perfect Bonus
From Sonic Retro
Blue Sphere
There is no Perfect Bonus in Blue Sphere, as there is no score in this game. However, collecting all rings in a stage allows the player to see the difficulty level of the stage just completed and allows them to skip ten stages.
Sonic Adventure 2 (Battle)
If the character gets all the rings in any action stage, except for boss levels, the character gets an automatic A rank.