SEGA Superstars Tennis

In the Superstar adventure mode, complete the final challenge in the Sonic the Hedgehog court (doubles tournament) to unlock this Achievement, and unlock Shadow.

I just wanted to list off all the minigames you have to go through and beat (beat opponent or get the target score):

Singles Match (beat opponent)
Singles Tournament (beat 3 opponents) Collect Rings (score 30 or more in 45 sec)
Collect Moving Rings (score 25 or more in 45 sec)
Dodge Balls (score 30 or more in 60 sec)
Collect Rings in Order (score 30 or more in 60 sec) Chaos Emerald Dash (collect 5 chaos emeralds in 45 sec)
Singles Match (beat opponent)
Heads Up (score 25 or more in 60 sec)
Speed Rings (score 100 or more in 60 sec) Dodge Balls 2 (score 45 or more in 90 sec)
Ring Chase (score 100 or more in 60 sec)
Score with Rings (score 4000 or more in 3 lives)
Tournament Doubles (beat 2 opponent teams)
after winning the Doubles tournament, you unlock Shadow and get the achievement
videos are from Reteulo-V on YouTube