Stunt GP Codes -

Forkster:
Successfully complete championship mode and get ranked first in points. Then, finish track 21 in second place.

Formula 17:
Finish time trial with a time better than the best lap ghost.

Stunt Car:
Complete all routes in arcade mode.

Worms:
Successfully complete mobile championship mode and get ranked first in points. Then, finish track 21 in first place.