The requirement for the December 2016 24-hour contest is "charcoal":
https://boardgamegeek.com/thread/1682701/24-hour-contest-december-2016
Tips & Resources for Board Game Designers
The requirement for the December 2016 24-hour contest is "charcoal":
https://boardgamegeek.com/thread/1682701/24-hour-contest-december-2016