A large black monster created by Vvelkkæn, the Bone King, to guard Celen Island. It's been around since the eternal Celen winter in the 18th century and protects the frozen wasteland. Ever since the 1970s, researchers have swarmed the snowy wasteland to monitor its abnormal infinite storm. Kolvverin attacks anyone it sees, especially scientists. It doesn't attack any of the bone king's other monsters tho and is deeply respectful to them.