Completing the Champions Cup of the World Open gives the character you played as a star, enhancing their abilities.
- Star Character - Beat the Champions Cup as a given character
- Baby Mario Complete 1-3 in the Super Mario Tennis Special Game.
- Baby Peach Complete the Pro Rings level of the Ring Shot Special Game.
- Dry Bowser Complete the Inksplosion level of the Ink Showdown Special Game.
- Luma Complete the Superstar level of the Galaxy Rally Special Game.
- Bee Mario Costume Turn 8 Mario characters into star characters
- Birdo Costume Beat an Ace opponent in a singles Exhibition match
- Boo Costume Buy 100 different items in the item shop
- Bowser Costume Earn 50 Victory Medals from Online Multiplayer Open Matches
- Bowser Jr Costume Earn 20 Victory Medals from Online Multiplayer Open Matches
- Cloud Mario Costume Turn 10 Mario characters into star characters
- Daisy Costume Collect 700 ring points in Ring Shot Callenge with another player
- Diddy Kong Costume Meet 20 Mii characters via Streetpass
- Donkey Kong Costume Meet 50 Mii characters via Streetpass
- Dry Bowser Costume Earn 100 Victory Medals from Online Multiplayer Open Matches
- Fire Mario Turn 2 characters into star characters.
- Goomba Costume Add 100 items to the item-shop shelves
- Luigi Costume Beat the Star Final Cup Tournament in Doubles
- Luma Collect 1500 coins in the Galaxy Rally Challenge Special Game..
- Mario Costume Beat the Star Final Cup Tournament in Singles
- Peach Costume Collect 800 ring points in Ring Shot Callenge
- Petey Piranha Costume Reach 50 returns in the Ink Showdown Challenge
- Propeller Mario Turn 5 characters into star characters.
- Tanooki Mario Costume Turn 15 Mario characters into star characters
- Toad Costume Reach a total of 50000 coins
- Waluigi Costume Collect 800 Coins in Super Mario Tennis level 2-4
- Wario Costume Collect 800 Coins in Super Mario Tennis level 1-4
- Wiggler Costume Earn a total of 5000 points in Online Multiplayer Open matches
- Yoshi Costume Use QR Code from official Nintendo website
- Galaxy Arena Crystal Court Complete the Final Cup in the Star Open tournaments.
- Galaxy Arena Morph Court Complete the Final Cup in the Star Open tournaments.
Unlockable CPU Difficulties
For use in Exhibition mode.
- Ace difficulty Beat the Final Cup tournament.
- Pro difficulty Beat the Champions Cup tournament.
- 1-Up Mushroom Cup Beat all four cups of the World Open.
- Banana Cup Beat the Flower Cup tournament.
- Champions Cup Beat the Banana Cup tournament.
- Final Cup Beat the Shell Cup tournament.
- Flower Cup Beat the Mushroom Cup tournament.
- Ice Flower Cup Beat the 1-Up Mushroom Cup tournament.
- Shell Cup Beat the Ice Flower Cup tournament.