ICEAGE

Set to 24 different clues across 27 published puzzles, most often “When the Great Lakes were formed” — The New York Times, Sunday, 14 June 2009.

6 letters

Every clue on record, most used first

When the Great Lakes were formed2 times
The New York Times — Sunday, 14 June 2009
When mastodons disappeared2 times
The New York Times — Wednesday, 12 November 2008
Cooling-off period2 times
The New York Times — Saturday, 24 September 2005
Freezing periodonce
The New York Times — Monday, 29 June 2009
Wintry stretchonce
The New York Times — Friday, 3 April 2009
Period ending about 9000 B.C.once
The New York Times — Monday, 14 July 2008
Time of advancing glaciersonce
The New York Times — Monday, 28 April 2008
Cold spellonce
The New York Times — Saturday, 30 December 2006
Glacial periodonce
The New York Times — Tuesday, 4 July 2006
The Pleistocene Epoch, familiarlyonce
The New York Times — Sunday, 2 April 2006
The big chillonce
The New York Times — Thursday, 8 April 2004
Frigid timeonce
The New York Times — Tuesday, 2 December 2003