This Christmas Vacation t-shirt shows one of Clark Griswold's moose mugs. The shirt reads Filled With Holiday Spirit. Marty Moose was first introduced as the mascot for Walley World in the 1983 classic National Lampoon's Vacation. In the 1989 holiday classic Christmas Vacation, Clark Griswold was seen drinking eggnog out of a Marty Moose mug. National Lampoon's Christmas Vacation is one of the most popular Christmas movies of all time. Everyone will immediately know that you are a fan when you wear this Filled With Holiday Spirit Christmas Vacation T-Shirt!