battle-scarred vs hardened

battle-scarred

adj
  • Having scars or other damage received in battle 

hardened

adj
  • Having extra defences against attack; highly fortified. 

  • Inured; toughened. 

  • Firmly established or unlikely to change; inveterate. 

  • Unfeeling; pitiless; callous. 

How often have the words battle-scarred and hardened occurred in a corpus of books? (source: Google Ngram Viewer )