Earn platinum medals by performing the corresponding tasks:
PLATINUM MEDAL - HOW TO UNLOCK
Cone Zone - Get 80 scoops.
Veggie Guardin' - Defeat mole king.
Skip Skimmer - 180 Skip total for the 5 rounds.
Pose mii plus - Get 900 points.
Trigger twist - Get 25,000 points on the "all stages" selection.
Jump Park - Have a 1:30 completion time on level 3.
Teeter targets - Complete level 30.
Spooky search - Get 1,500 points on level 3.
Wind runner - Get 200 points on level 3.
Treasure twirl - Get 8,250 points on level 3.
Flutter fly - Get 950 points.
Star shuttle - Complete level 30.
-Earn 6 Platinum medals by getting the Dolphin dash title screen demo. Wait about 30 seconds and one of them will appear.
-Earn 12 Platinum medals can be earned when the loony cycle title screen demo is playable.