Historical clue formulations

• Some venomous snakes — 2023-12-05
• Venomous snakes with zigzag patterns on their backs — 2020-12-08
• Venomous vipers — 2020-09-28
• Venomous vipers — 2019-11-27
• Dangerous vipers — 2017-11-26
• Poisonous snakes — 2017-09-17
• Milk snakes — 2008-01-30
• Puff ___ (Old World menaces) — 2006-03-05
• ___-tongue (small fern) — 2005-07-02
• Dangerous biters — 2002-08-22
• Bean counters — 1997-10-12
• Common vipers — 1997-03-25
• Venomous vipers — 1996-09-23
• Vipers — 1995-10-01