Mono-morphia

Mono-morphia was a disease that affected Whifferdills' ability to change shape. It prevented any shape changing until the disease wore off, leaving the sufferer in the form it had when it contracted the disease. The disease vector was unknown and the length of suffering varied enormously. Frobisher was affected by mono-morphia and was stuck in the form of a Penguin. (DWM: Genesis!) The disease wore off partially before returning to reaffect his abilities. (DWM: Changes, Profits of Doom)
 * It is unknown if mono-morphia only affected the whifferdill or if it acted against other shape shifting species like their relatives the kymbra chimeras.