The 'bake' and 'obake' are also used for good luck brought by chance, in which case the meaning includes not only a change in the subject concerned but also an expectation of change brought about by a speculative spirit as well as fortune-telling that the subject would change for the better.
偶然に訪れる幸運にも、この「化け」や「大化け」が使われているが、そのときには対象そのものの変化だけではなく、期待値が大きく好いほうへ変化する、という射幸心や占いなどとも、結びついている感情ともいえる。