In this festive heavyweight special episode, Carter Oosterhouse judges displays created by Nauticus' Winterfest, Imaginarium and River of Lights, all vying for the $50,000 grand prize and "Light Fight" trophy.

Mine shaft filled with holiday spectacles; a blow mold-filled design; an array using 115,000 lights.

A wonderland filled with whimsical characters; a dancing light show; a design with Santa's cottage.

It's the most wonderful time of the year. The Martin, Horn and Vistalli families go head-to-head for the most spectacular holiday displays in hopes of earning the $50,000 grand prize and "Light Fight" trophy as Carter Oosterhouse judges.

Four families will compete each week to transform their homes for the holidays in just 21 days.

The Blasko, Slankard, Buchanan and Clinkscales families compete

Four families will compete each week to transform their homes for the holidays in just 21 days.

The Masone, Cook, Rezendes and Joules-Cornetti families compete.

Displays include a Magic Kingdom-inspired light show, a high-tech homemade light show and more.

Displays in Escondido, Calif.; Waco, Texas; Bismarck, N.D.; and Ambler, Penn.

Displays include a Northwest-theme, classic Christmas toys and a theme park design.

Holiday displays in Jenks, Okla.; Boise, Idaho; Fontana, Calif.; and Brownsville, Tenn.

Holiday displays in LaVerkin, Utah; Wilmington, Mass.; St. Louis, Mo.; and Deer Park, N.Y.

Displays include the Nagy family with their high-tech light show dedicated to their dog and packed with a towering joy sign, a ballet of snowflakes on the roof and an interactive talking snowman, in Waterford Township, Michigan; the Nirschl family with their heartwarming Christmas display, dedicated to family and all the things they love, including inflatables, a magical archway, and a festive interior.

Four families transform their homes for the holidays in hope of winning $50,000.

The Torres family show their pirate-themed Caribbean Christmas display, featuring a two-story handcrafted castle that covers the facade of their house, a life-sized pirate ship with cannons and a 35-foot mast, in Henderson, Nevada; the Murphy family, with the help of their art class students, transform their house into Christmas art with over 400 precisely cut figurines, 75 extravagant scenes and a massive 25-year-old Cinderella castle.

Competing displays include an array of decorations, animatronics and a tribute to veterans.

Christmas DIY details; an elegant animated display; lighting 70-foot trees for charity.

A Mardi Gras Christmas; rooftop carolling; the true meaning of the holiday.

Judge Taniya Nayak continues the holiday festivities as the Irvin, Lunar and Kopatz families battle for the $50,000 grand prize and coveted "Light Fight" trophy.

Four families transform their homes for the holidays in hopes of winning $50,000.

Four families transform their homes for the holidays in hopes of winning $50,000.

The Sablich family creates a North Pole experience featuring Santa's Workshop in Fort Lauderdale, Florida; the McGonigle family spaces light strings exactly three inches apart, plus a gingerbread house and 102 dalmatians in Plantation, Florida; the Fester family displays 750,000 lights, 99 Christmas trees, and more exciting surprises in Panama City Beach, Florida; and the Alred family displays light strands 75 feet high in Jacksonville, Florida. Judge Taniya Nayak decides the winner.

Competing displays include a tree with more lights than the one at Rockefeller Center.

Holiday displays in Egg Harbor Township, N.J.; Lehi, Utah; East Peoria, Ill.; and Glendale, Ariz.

Holiday displays in Alexandria, VA, Corriganville, MD, Burbank, CA and Surf City, NC.

Holiday displays in Brooklyn, NY, Atlanta, GA, Independence, KY and Winter Haven, FL.

The heavyweights division has the Bentley family with “Bentleyville,” a 22-acre decorated city park with 5 million lights, over 200 wireframes and the tallest man-made mega tree in the country, in Duluth, Minnesota; the Winter family with “Cambria Christmas Market,” a Germany-meets-California display, filled with gift shops and food stalls, plus an enchanted forest spread over 25 acres.

The Ford Family presents a Nightmare Before Christmas display with a scary toy factory and more in Mission Viejo, CA; the Quintero Family presents a whimsical Christmas meadow with flowers radiating Zen and peace in Atwater, CA; the Aromin family puts on a synchronized light show with a 12-foot replica of the Mickey Ferris Wheel in Fairfield, CA; and the Levy family displays their symmetrical diamond-shaped lights in Sacramento, CA. Judge Carter Oosterhouse chooses the winner.

Families showcase festive displays, including handmade plasma icicles and a 16-foot snow slide.

Families showcase festive displays, including a laser show and dancing trees that are 45-feet tall.

The Relvas family creates a Swiss Alps Christmas town with over 400 figurines in Ladera Ranch, California; the Christensen family showcases their "Frozen" inspired holiday display and waterfall of lights in Citrus Heights, California; the Clark family presents a display of seven themed areas from LED palm trees to a whimsical forest in Clarksburg, California; and the Berndt family puts on an interactive display featuring a working train, penguin slide, and giant claw lift that distributes presents to the children in Santa Rosa, California. Judge Carter Oosterhouse make the decision.

Judged by Taniya Nayak, the tree-mendous Christmas decor competition heats up as the Hak, Paul and Riera families put their creative skills to the test to win the $50,000 grand prize and "Light Fight" trophy.

Families transform their homes for the holidays in hopes of winning $50,000.