Complete the game in Marathon Mode.
Collect a duck in Marathon Mode!
Collect four ducks in a single Marathon playthrough.
Get all the ducks in a single Marathon playthrough.
Complete a level without scoring any points at all.
Get some meat from inside a wall while in Marathon Mode.
You got the Book of Wisdom in Marathon Mode!
Use a certain well-known cheat code.
Beat the game without losing a life and getting all the special items in a single Marathon playthrough.