While the general Hall of Fame is an ongoing competition, we like to run time-definite competitions between updates that we call Gauntlets.
For december we got again two new ones, one major, one minor:
For the G-Major CXXXIX, you need to play as Harald of Denmark on a small shuffle map on Immortal level, and you need to win via a science victory. The deadline is December 31, and you can find more information here.
For the G-Minor CCXII, you can play as any leader on a tiny small continents map on chieftain with quick speed, with some defined competitors (see thread) and a diplomacy victory. Also here the deadline is December 31, and you can find more information here.