Jump on the duck
Go to 2:58 in this video, and then...
-- Jump on the duck.
-- They're turtles, not ducks!
-- But this is Super Mario's Duck Hunt, isn't it?
-- No, those are two different games in one Game Pak. They're Koopas, and Koopas are turtles.
-- They're ducks.
-- Ducks don't have shells.
-- They're shell-ducks. I think I saw some in that Avatar cartoon, and here are some more.
-- I give up...