Unlocking the Star Cup:
     Complete Both the Mushroom and the Flower Cups with a gold cup to
unlock the Star Cup.

Unlocking the Special Cup:
     Complete the Star Cup with a gold cup to unlock the Special Cup

Unlocking the Feather Cup:
     Complete  the  Shell  Cup  and  Banana Cup with a gold trophey to
unlock the Feather Cup

Unlocking the Lightning Cup:
     Complete  the  Feather  Cup  with  a  gold  trophey to unlock the
Lightning Cup.

Unlock Daisy:
     Complete the 50cc Nitro Grand Prix cups with a rank of A or higher

Unlock 3 choice karts:
     Complete the 50cc Retro Grand Prix cups with a rank of A or higher

Unlock Dry Bones:
     Complete  the  100cc  Nitro  Grand  Prix cups with a rank of A or
higher to have Dry Bones selectable as a racer

Unlock Waluigi:
     Complete  the  100cc  Retro  Grand  Prix cups with a rank of A or
higher to have Waluigi selectable

Unlock the Mirror Class Cups:
     Complete  the  150cc  Nitro  Grand  Prix cups with a rank of A or
higher to unlockt he Mirror class set

Select 7 karts:
     Complete  the  150cc  Retro  Grand  Prix cups with a rank of A or
higher to select among 7 karts.

Unlock R.O.B:
     Complete  the Mirror Class Nitro Grand Prix cups with a rank of A
or higher to have R.O.B selectable

Select among all karts:
     Complete  the  Retro  Class  Grand  Prix cups with a rank of A or
higher to select all the karts for any character

Unlock the 7th set of Missions:
     Complete  the  previous  6  set  of  missions with a Star Rank or
higher to unlock the 7th set of missions.