The following characters' costumes become available options when you use them to win 5 Golds or/and 1st medals in any Olympic/Dream Events.

Unlock Amy's Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Amy.

Unlock Blaze's Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Blaze.

Unlock Bowser Jr.'s Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Bowser Jr.

Unlock Bowser's Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Bowser.

Unlock Daisy's Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Daisy.

Unlock Donkey Kong's Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Donkey Kong.

Unlock Eggman's Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Eggman.

Unlock Knuckles' Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Knuckles.

Unlock Luigi's Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Luigi.

Unlock Mario's Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Mario.

Unlock Metal Sonic's Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Metal Sonic.

Unlock Peach's Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Peach.

Unlock Shadow's Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Shadow.

Unlock Silver's Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Silver.

Unlock Sonic's Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Sonic.

Unlock Tails' Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Tails.

Unlock Vector's Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Vector.

Unlock Waluigi's Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Waluigi.

Unlock Wario's Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Wario.

Unlock Yoshi's Costume:
Win 5 golds or/and 1st medals in any Olympic/Dream Events with Yoshi.

Complete the following tasks to unlock the corresponding Mii costume which will change your Statlines to match the character.

Unlock Espio:
Buy the Black Shopping Card from the Secret Store.

Unlock Bee Mario:
Buy the Black Shopping Card from the Secret Store.

Unlock Charmy:
Buy the Gold Shopping Card from the Secret Store.

Unlock Dry Bones:
Defeat Team Dry Bones in Team Festival mode Curling.

Unlock Diddy Kong:
Buy the Platinum Shopping Card from the Secret Store.

Unlock Rouge:
Defeat Rouge in Individual or Team Festival mode Figure Skating.

Unlock Dry Bowser:
Defeat Team Dry Bowser in Individual or Team Festival mode Ice Hockey.

Unlock Omega:
Defeat Omega in Individual Festival mode Speed Skating or Team Festival mode Short Track Relay.

When you have accumulated a few hours of game play or completed a Festival mode you will receive a note about a secret shop. Go to the Shopping district and stop the camera between the far left and middle buildings then aim the pointer at the shop down the alleyway between the two and you will be able to access the secret shop.

The following Emblems are awarded when you complete the corresponding task.

High-Speed Emblem:
Exceed 100kmph in the Bobsleigh.

Sprinter Emblem:
In Speed Skating 500m get 5 or more 'Perfect' ratings in a row.

Showtime Emblem:
In Dream Figure Skating get 10 or more 'Perfect' ratings.

Ice Spirit Emblem:
In Figure Skating get 10 or more 'Perfect' ratings.

All Flags Emblem:
On the Alpine Skiing Giant Slalom pass through ALL the gates.

Combination Emblem:
In the Speed Skating Short Track Relay get a 'Great' or better on ALL exchanges.

Performer Emblem:
In Snowboard Cross perform 5 or more tricks.

Cool Trick Emblem:
In the Snowboarding Halfpipe perform 15 or more tricks.

Festival Master Emblem (Ind.):
Clear individual Festival mode with 200 points or more.

New Record Emblem:
In any event beat an Olympic record or default best record.

Non-Stop Emblem:
Reach the finish in Skeleton without crashing into the wall once.

Reversal Emblem:
In the Speed Skating Short Track 1000m go from 4th to 1st.

Special Action Emblem:
Perform 3 or more 'special actions' in a match with one character.

Rocket Emblem:
Pull off a 'start dash' in any event.

These features become available options when you complete the correspoinding tasks. There is more than one way to unlock each Dream Event and once unlocked will also become accessible in Single-Event mode.

Unlock Dream Snowball Fight:
Reach Day 9 of Individual Festival mode.

Unlock Dream Gliding:
Reach Day 11 of Individual Festival mode.

Unlock Dream Short Track:
Reach Day 12 of Individual Festival mode.

Unlock Dream Snowboard Cross:
Reach Day 16 of Individual Festival mode.

Unlock Dream Figure Skating:
Reach Day 16 of Individual Festival mode.

Unlock Dream Ski Jumping:
Medal in Dream Alpine in Individual Festival mode.

Unlock Dream Alpine:
Get a medal in ALL the Alpine Skiing and Freestyle Skiing events, or alternately reach Day 3 of Individual Festival mode.