Mettaton's Legs became a viral sensation following the release of the indie RPG Undertale in 2015. During the battle with Mettaton EX, the character's long, pink, and incredibly stylish legs become a focal point of his design and dialogue, specifically the line 'Who needs arms with legs like these?' Fans quickly turned this into a meme by photoshopping Mettaton's legs onto various objects, people, and other video game characters to give them an instant boost of glamour. It represents peak confidence, dramatic flair, and the 'leg day' fitness trope, remaining a staple in the gaming community for its sheer absurdity and charm.