Historical clue formulations

• Guard — 2023-06-11
• Guard — 2022-06-19
• Who might say "Who goes there?" — 2022-04-26
• Halter? — 2022-03-05
• Ever-vigilant sort — 2009-04-04
• One whose speech is halting — 2005-09-04
• Halter? — 2005-01-19
• One who might issue a challenge — 2004-03-17
• "Halt!" caller — 2003-03-11
• Halter? — 2002-11-24
• Halter? — 2000-07-01
• Guard — 1997-05-20
• Guard — 1996-01-08
• Door stopper? — 1994-02-18