HEAT oven to 350°F.
CHOP 14 cookies coarsely. Beat cake mix, water, oil and egg whites in large bowl with mixer on low speed just until moistened. Beat 2 min. on high speed. Stir in chopped cookies. Spoon batter into 24 paper-lined muffin cups.
BAKE 20 to 25 min. or until toothpick inserted in centers comes out clean. Cool in pans 10 min.; remove to wire racks. Cool completely.
CUT 2 pieces off each of the remaining cookies to form a "V"-shaped reindeer face. (Save cut-off portions for another use.) Attach 2 pretzel twists to each of the cookies with some of the melted chocolate for the reindeer's antlers. Decorate the face using red hot candies, chocolate chips and sprinkles, attaching with melted chocolate as needed. Refrigerate until set.
SPREAD tops of cupcakes with frosting. Insert reindeer face into the top of each cupcake just before serving.