Donkey Kong Country: Speak No Evil, Dude (2000)

While cutting through the mine tunnel, Diddy overhears King K. Rool's plans to take over the island. Unfortunately, the symptoms for Kongo Bongo Gone Wrongo disease have begun and Diddy hasn't been vaccinated. By the time he reaches Donkey Kong to warn him, he is at stage four of the disease and Diddy has lost his voice.