In the legend of Xiao Bingbing, the King of Skeleton and the King of Bone are two different heroes. They are all related to skeletons, but their attributes, skills and characteristics are different. The original version of "The Legend of Xiao Bingbing" is called "The Legend of the Knife Tower", which is a card mobile game developed by Shanghai Lilisi Technology Co., Ltd. and operated by Beijing Zhongqing Longtu Network Technology Co., Ltd.