Back when I was a kid I had access to a video tape that had 4 Nelvana animation specials on it.
Devil and Daniel Mouse.
Rom-E-O and Jul-E-8
Please Don't Eat the Planet.
and Cosmic Christmas
Cosmic Christmas is just one of those long lost Christmas specials that approaches the "What is the true meaning of Christmas?" question in a unique and fun way. It goes a little overboard sometimes when giving you the message, and with the religious significance behind the holiday, but I really do enjoy the animation and the voices. It was also a lot darker than a majority of Christmas specials. And not just in tone, but in the brightness of the animation as well. Most of the action happens Christmas Eve in the dark woods, so it definitely doesn't always have the bright cheeriness to it you see in other specials. Which is definitely the point of it. When it does get brighter, it's when people are coming to terms with the true meaning of Christmas.
Oh. And it's about aliens visiting Earth looking for Christmas.
Youtube it.