INIS

Set to 3 different clues across 4 published puzzles, most often "Last one ___ a rotten egg!" — The New York Times, Tuesday, 11 February 2003.

4 letters

Every clue on record, most used first

"Last one ___ a rotten egg!"2 times
The New York Times — Tuesday, 11 February 2003
"Last one ___ ..."once
The New York Times — Friday, 28 March 2008
"Last one ___ ?"once
The New York Times — Friday, 6 January 2006