It's not every day we spot celebrities. And when we do happen to see them, it's challenging to whip our phones out to snap a decent picture. At Madame Tussauds Las Vegas, not only will you have enough time to take a picture with your favorite superstar (or superhero), but you'll be sure to fool your friends back home, too. The 100-plus wax replicas look so real that you'll find yourself taking a second glance.The best part of the two-floor, 30,000-square-foot museum is having the chance to get up-close and personal with each celebrity. Touching is highly encouraged. After all, you want your pictures to look as realistic as possible, right? Some replicas have fun little features included. For instance, if you touch Jennifer Lopez's backside, she blushes.Some guests get a bit carried away with the whole interactive element, especially after a few trips to the bar located inside the museum. Aside from the usual lipstick marks and scratches on the replicas, visitors in the past have even styled or braided hair. Can you picture Lindsay Lohan in pigtails? Overly eager guests have even shattered wax figures like Harrison Ford and Jenna Jameson to pieces. Fortunately, Madame Tussauds Las Vegas has a team of talented studio artists to repair such blunders. However, if it's beyond repair, the team has to send the figures back. Keep in mind while you're here that it's OK to touch -- just don't be that guy.Madame Tussauds Las Vegas features tons of your favorite celebrities, from musicians and movie stars to sports figures and superheroes. Though a partnership with Marvel Comics, Madame Tussauds has assembled some of The Avengers. A multi-sensory Marvel 4-D Theater allows film viewers to feel the action (and even get wet) as the superheroes save Las Vegas from destruction.In the Hollywood/A-list room, get face-to-face with stars such as Sandra Bullock, Matthew McConaughey, Brad Pitt, Angelina Jolie, Hugh Hefner and Jamie Foxx. If you're a big music fan, then you're in luck. Madame Tussauds features musicians from all genres, from Gwen Stefani and Britney Spears to Snoop Dogg and the late Tupac Shakur. Have fun singing karaoke-style as "American Idol" judge Simon Cowell watches on with a scowl.In the sports room, shoot hoops next to the towering Shaquille O'Neal figure or putt with Tiger Woods. The Vegas showroom showcases stars like Liberace, Wayne Newton, Frank Sinatra, Siegfried & Roy (complete with a white-striped tiger!) and Celine Dion.Some celebrities get directly involved in order to make their figure. R&B sensation Beyoncé worked closely with Madame Tussauds artists in London as they replicated her hair color, make-up, body type and complexion. Gwen Stefani teamed with in-house studio artists at the Las Vegas location to help achieve the style of her wax figure. Fergie from Black Eyed Peas even donated one of her dresses to the museum.The process of making a figure is lengthy -- it can take anywhere from four to six months. Once researchers conduct surveys on who should be included in the attraction, they find out as much as they can about the celebrity including how they pose in pictures, common facial expressions and their hairstyle and clothing preferences.If he or she is able, the celebrity comes in for a sitting. The stylists take more than 150 measurements and 200 photos. This is also an opportunity for artists to match the hair and eye shade perfectly. For the face, the team uses oil-based paints and applies it in layers, creating a realistic skin complexion. Fun fact: The body is not only made of wax, but also steel and clay.To keep the attraction new and exciting, Madame Tussauds adds or rotates new figures frequently. There are dozens of locations throughout the world including Atlanta, New York, Shanghai, London and Amsterdam, to name a few.