Platdude found himself having to traverse some levels. Within each level were a set of Xmas trees, and he found that if he turned all of the Xmas tree lights on, he could get out the door.

You played it last year, and now it’s back in a really minor way! 8 extra levels of varying difficulty, with a new “Light up all the Xmas Trees” theme, and a bit of snow.

http://www.drunkencoders.com/compo/index.php?page=entries