In this case, the mage turns time back upon itself within a certain area of effect. Story-wise, you might see Lee Ann cut a complex glyph in the air with her lotus sword; everything within the room stops moving except for Lee Ann herself, and then it all “rewinds” to a given point in time while Lee Ann changes the actions she would have taken otherwise.

In game terms, time loops count as Magickal Feats of Time, with bigger reversals becoming bigger feats. Repeated time-loops suffer the Repeated Time Effects penalty described above.