Now, be attentive, my dear cheater! I'm going to teach you how to make Christmas in Darwinia cheat! It's not a complicated task. So, read this carefully:
Set your PC clock to December 25th or play the game this day. Go to any level you like and you will see that there's snow in each level. Find a Darwinian and about 50 percent that he will be wearing a Santa's hat! How do you like it? ;)