Every day from 9 o'clock German time you can click on the golden star of a christmas card and receive teleportinfos to the region of the day, where a snowman offers you a freebie at the landing point or you will get a freebie from the calendar.

All freebies and landmarks are available until the 29. December 2017
Here is the Inworld calendar: greenworld.online:9022:StartPunkt

Further information: http://startpunkt.greenworld.online/winterzauber (in German)