Historical clue formulations

• Enliven — 2020-06-26
• Invigorate — 2011-04-11
• Add zing to — 2010-03-07
• Animate — 2009-02-22
• Give some zing — 2008-06-15
• Enliven — 2004-07-10
• Give some zing — 2002-06-12
• Animate — 2000-03-16
• Animate — 1998-03-21
• Enliven — 1994-07-03