fierce vs going off deep end

fierce

adj
  • Excellent, very good. 

  • Exceedingly violent, severe, ferocious, cruel or savage. 

  • Resolute or strenuously active. 

  • Of exceptional quality, exhibiting boldness or chutzpah. 

  • Threatening in appearance or demeanor. 

adv
  • Extremely; very. 

going off deep end

How often have the words fierce and going off deep end occurred in a corpus of books? (source: Google Ngram Viewer )