Chicken Invaders 5 - Christmas Edition

As the sun sets on Christmas Eve, everyone on Earth impatiently awaits the dawn of Christmas Day. However, invading intergalactic chickens have hatched a plan to make sure this dawn never comes. No opening of presents on Christmas morning, no riding a one-horse sleigh, no Christmas dinner. No, no, no, this won't do. Looks like you'll have to step up once more and save Christmas Day (quite literally)!