Dark Ages

lol, so it can be a Dryad during the day and an Ogre at night? )) Mentor, please explain.

No, firstly, there isn't a clear connection to day and night. Secondly, it refers to wildlife, not different types of humanoids. Of course, there are limitations ("I want to be a dragon" won't work, for example), but on the other hand, many creatures can be significantly enhanced. In another thread of "Own Game," people encountered a werewolf-bat, for example, which was larger than a regular bat.
Wolves are one of the most common versions of a werewolf, of course.