Yin-Yarn is the main villain of the Kirby game Kirby's Epic Yarn. He is an evil sorcerer who wreaks chaos and havoc in Dream Land and Patch Land. When Kirby tries to stop him he traps Kirby inside a sock that leads him to Patch Land, where Kirby's body transforms into yarn. A bit later, Kirby realizes that air goes through yarn, which forces him to use the yarn whip and transformations with yarn instead. Kirby and Prince Fluff set off to recover seven pieces of yarn, defeat Yin-Yarn, and bring peace back to both Dream Land and Patch Land. Yin-Yarn is the boss of Dream Land and is fought in two forms: first, he attacks Kirby and Prince Fluff in his normal form. Secondly, he attacks them as Mega Yin-Yarn, leaving Kirby and Prince Fluff hopeless. Suddenly, Meta-Knight flies by, dropping a Tankbot Metamortex, turning them into a Tankbot to fight and defeat this evil incarnation. His name is a pun on yin yang.