化ける

to take the form of (esp. in ref. to a spirit, fox, raccoon dog, etc.); to assume the shape of; to turn oneself into; to transform oneself into

to disguise oneself (as)

to change (into); to transform; to metamorphose

to change radically (for the better); to transform; to improve dramatically and unexpectedly (e.g. of an actor, sportsperson, stock price); to make a complete turnaround